ezchronicles

Landing Speeds II - Slats and Flaps?

2008-03-06T17:11:00.000-08:00

So I’m in shade tree mechanic mode, sitting out here under this tree again. Waiting. I have been here before, long ago rehearsing the final steps to install the VariEze wings straight without the 10.9 inches of anhedral. Wondering whether extending the strakes forward would cause a deep stall problem like some larger canard planes were experiencing at the time. Envisioning what it would take to lower the cruise attitude slightly, more like the LongEZ. Later there was some pretty productive cooling contemplation, and some induction deduction. All routine now.

I’m literally living in your ‘slower landing’ arena, Marc. Changing to a 4000 foot runway from 6000, my approaches are a little more deliberate. I love it. So as a shade tree mechanic, besides thinking about the slower landing speeds, I get to consistently practice them. Coming in on final the other day with the nose attitude ten knots slower, the canard was fine but it sure seemed that having the wings lift a little more with the speed slower and the rear end a little higher would have been a good thing.

So I’m under the shade tree here again, mentally lingering a while with your lowering stall speed question, waiting for the solid elements to fit into place and for everything else to fall of its own weight, so to speak.

How to improve the wings for lower landing speeds.
Flaps? Slats? I have a plan, a design, several of them. I wonder if adding slats and flaps to the Eze main wing would provide a simple overall benefit, or if it would include undesired side effects. I don’t get to think about this as much as I’d like, but do wake up thinking about it every week or so. Just like the good old days.

I am waiting, expecting to be lured over the edge by someone that knows what they are doing; to settle the result of adding lift to the main wing; the result on the canard; the result on approach attitude, waiting for the physics to settle in as with the previous mods.

Basic Concepts
Marc, your initial 1 January note mentioned changing things on the wing without changing the canard. Touchy territory in Ezeland. At that time I was able to quickly work up a basic, socially acceptable position paper primarily denouncing messing with the critical canard/wing relationship. Speech #3 as my kids call those kinds of well worn monologs. Re-reading and reworking, the direction changed as two conflicting concepts met for me for the first time.

One is a position that I have nodded in agreement with for years at Eze fly-in bull sessions.
The concept was that if the weight of the engine were removed from the back, the canard would not have the authority to hold the nose up. The plane would go pure vertical nose down. Surely everyone knew this must be true.

But several years ago an actual event established the truth. You have all read about the incident right? If I remember correctly, a North Carolina VariEze was making a 200 mph-ish low pass, felt a jolt and power loss, and landed on a parallel runway.
Wondering what the heck, the pilot got out and saw dangling wires in back and fluid on the ground. He put the nose on the ground and walked back and was astonished to find that there was no lower cowl - and no engine. A crash crew pickup pulled up with the engine in the bed. I remember him attributing the engine being pulled off by a failed male inlet and lower cowl. Must have been especially interesting for the first time flyer in the back seat.

Interestingly, he stated that control response during the landing gave little or no indication that the engine had departed the aircraft. Others claiming experience in this arena seem to agree. So what about the unrecoverable nose down dive? Obviously the nose is being held up by trading off speed. There are evidently some areas of GU canard operation that haven’t been fully documented. And the area of interest here looks like one of them.

The point?
Everything in my eze 'training' would indicate that more complex wings would unquestionably require a more complex canard. Therefore, forget the flaps! But under the shade tree here there is at least a momentary hesitation on whether the canard might not have to be changed in conjuntion with the wing in the course of reducing landing speed. This is a very interesting moment.

Marc, your question was,
>>has anyone succeeded in lowering the stall speed of the longez?<<

As I mentioned in the Hangar Talk note, it has been done. They actually did that with the LongEZ itself. The fledgling VariEze had to be landed too fast. They modified the wing, resulting in a different wing with less sweep and about a third more area. It carried the added starter and alternator and provided the desired lower landing speed and distance.

So, an Eze wing has been modified to provide a lower ‘stall’ speed. The point here is not to make a play on words, but to try to grasp the fact that no change was made to the GU canard. It still operated almost identically with higher lift wings. Heavier follow-on aircraft had 'normal' handing qualities with the same GU canard.

While some may have silently nodded through this long ago, others of us have quite a ride realizing the implications here. Could another similar reduction in ‘stall’ speed be made using ‘another’ redesign of the main wing (maybe slats and flaps this time?) – while still retaining ‘normal’ canard operation? If so, this is a much simpler mod.

Now bring in the 200 lb engine weight change where the canard provided 'fairly normal" pitch control, and you have a pretty interesting situation.

Yes, everything that is preached about the canard/wing relationship is unchanged, firmly in place, required as designed. I'm watching to see how this new element relates, and if wings optimized for landing would actually benefit the relationship.
(For two months this subject has had me wondering how many canard aircraft actually have had the stall resistance (CG) confirmed by their current owner/operator at all).

The practicality test is probably centered on what effect the added main wing flaps and/or slats actually does to approach attitude and speed and landing distance. This is what I was looking at and thinking about the other day on final with the nose fairly high. If the canard was operating with significant residual lift, couldn’t the rear be lifted a little, possibly with a move back toward the desired balance?

Much of the Eze evolution has resulted in the CG gravitating aft. Thus at full aft stick there is a higher nose attitude, with the main wing closer to stall. As mentioned in the CPs, early on, RAF’s solution for Shirl Dickey’s squirrelly landing problem was to add 12 lbs of ballast in the nose of his VariEze. Then further RAF tests showed that removing four inches off the tips decreased the canard lift capability to a just right relationship again, allowing removal of the 12 lbs.

Would adding lift to the main wing actually move the attitude more back toward an assumed (by me) middle attitude/CG sweet spot, where nose up attitude and main wing angle would still be appropriately canard limited-
Limited by a canard that has operated consistently through a significant range of applications.

Many similar mental explorations in the past have resulted in a door being gently but firmly closed against my nose. And my history of logic with these things is usually exactly 180 degrees off. We’ll see. A 24-inch long formula proving all this would certainly be impressive here.

It is interesting to imagine the variety of sugarplums dancing in Eze heads here right now. Maybe a 2000 lb LongEZ that can be landed at 40 mph!
However, in my mind over here on the other end of the spectrum there is an image of a wispy but tough 550 lb VariEze with a stock canard and articulating…even better, morphing wings, and tantalizing semi-short field capability.

I know this flap/slat stuff won’t work. Too complex. Too heavy. Too draggy. Too scary. Thank goodness. Because someone could really hurt themselves. Maybe it will just go away :)

But every once in a while, about half way through waking up, I peek up and see ghostly transparent spidery looking slats and flaps hovering around the ceiling, beaconing me out to the hangar. Thanks a lot Marc.

Bill James, Fort Worth VariEze

Lowering Landing Speeds

2008-01-21T20:05:00.000-08:00

Howdy Marc-

In your Hangar Talk note you said “I'm looking for ways to reduce approach speed and runway requirements. Has anybody had success with lowering the stall speed of a longez?”

A Long EZ in our hangar has Jim Price’s vortex generators on the canard and wings. The owner agrees with the advertised ten knots lower landing speed and a two knot loss at top end, with cruise basically unaffected. Sounds like the Price/NASA-developed VGs would do what you are looking for.

I do have another suggestion, at the end. Don't cheat, work your way down : )

The Trailing Edge Fences on my VariEze do provide slower lift off speed and shorter takeoff distance, and more comfortable approaches at about ten mph slower. However, their benefit is rarely experienced since I am more interested in takeoff energy, letting the plane lift off when it is ready, and usually adding a little speed on sporty landings. Both, out of the benefit arena.

I agree on getting up to speed, or more accurately ‘down’ to speed on landing discipline. Cheap thrills, and cheaper and probably more prudent than the kind of structural mods I think you might have in mind, which I would never be foolish enough to consider... more than every year or so : )

I’m up to about a thousand landings on the VariEze. Your topic reminds me of two learning experiences. Lesson One, in a power out approach, an EZ requires about 22 mph as a buffer to trade off in the flare. Two, to your topic of shorter landings, with appropriate application of that pilot stuff, a guy can make a slower approach and use power to subdue the rate of descent.

There is that very fascinating concept about pitch and power - that I will skip and just postulate that on this subject - a very slow landing approach, adding power will not necessarily make the landing rollout distance longer. The purpose of this note should be obvious, to stir the short landing juices from those in the know.

The 22 MPH Buffer
The first concept - In a power off approach, an EZ requires about 22 mph as a buffer to trade off in the flare. This report came from an F-16/EZ driver and could probably be found in the canard archives if someone wanted to bad enough. If I remember right, his conclusion was based on looking at the aftermath of an over gross EZ on takeoff attempting to make it back to the runway without power, with probably full left and full aft stick. The F-16 driver was generous enough to share what he learned after approximating the situation in his EZ.

We know the EZ is stall resistant. However, in the power off, fully deflected turn he reported a very high (unsurvivable) rate of descent. Assuming again that I am remembering correctly, he worked through a number of wings-level power off approaches in his plane. The take-away was the golden 22 mph tradeoff buffer. Over the years I have observed this to hold water.

Arresting Descent Rate With Power
I don't approach this type of landing lightly. I work into the 22 mph buffer gradually, and mostly complete these approaches by leveling off while still several feet in the air. In the past I occasionally made a few gratifying landings all the way to terra firma, but now feel no further need to take them all the way to touchdown. I can see making daring steep approaches into some exotic, out of the way strip, or maybe a no-nonsense precautionary landing, but these short srtip imaginings always conclude with the potential of an empty throttle and firmly thudded landing.

I do practice the short approaches. Getting ready for Rwy 02 at RR puts me on my best behavior. Back home when the wheelpants are off, I try to make the 1500 foot turn off. The point is minimal ground roll. But even more important than that is arriving back at the hangar with the gear attach hardware still in place.

Since this includes getting slower than the 22 mph buffer, the first step is at altitude to reconfirm the plane’s minimum speed, *per the operating manual and CPs*, looking for the ability to make gentle turns using combinations of aileron and rudder at full aft stick. Per design and with proper CG, with the canard at max pitch, the wings are still several degrees within their comfort zone.

For me, this min speed is approached very gradually with great care. In my plane, at full aft stick and low power the plane holds altitude, with the nose either nodding up and down a little or holding steady at a high nose attitude. Gentle turns can be made but my interest is that the wings can be returned to level, kinda like a guy would be doing during a landing.

You used to hear of folks doing abnormal things at this slow speed to see if the plane would depart, like making large, multiple control inputs with a purposefully out of limit CG and such, and then be surprised when abnormal things did happen. Not part of this discussion.

Knowing the plane’s minimum speed, plus 22 mph, gives the target power off approach speed where you still have the ability to flare and arrest the rate of descent. Since getting slower than this ‘min+22’ number is actually likely a little dicey, a guy can start out his practice at maybe 25 plus and work down. He may never choose to work very far down into the ‘min+ 22’ number. But this provides a target flare speed for an emergency landing. And an appreciation of need for the 22 mph buffer.

What this has meant to me over the years, especially on takeoff, is that upon a power loss I want to get the nose over. In any airplane on climbout, most folks are surprised how quickly speed drops and how much the nose must be pushed over to even hold speed, much less get up to a 22 mph buffer. Regaining speed at low altitude is tough.

The practice short field approaches start out aimed about a third of the way down the runway. At the slower speed, in the “power-flare”, throttle is used to slow and stop the descent rate several feet high. Once leveled off, sometimes a normal touchdown is made.

If taking it all the way down, timing and experience and luck during the throttle application will hopefully make it look like we did all that pilot stuff right.

The fun part to see here, contrary to common sense, is whether adding power in the flare can reduce the ground roll, or if the airplane is propelled further down the runway.
If you do this Marc, check out your starting “ability” to see how much time and money you saved : )

A potentially expensive element in play here is prop clearance. I have encouraged folks on their first front seat flight to put the extended nose wheel on a paint can sit in the plane and imprint that attitude for first-flight rotation attitude and approach attitude sight picture. But for more aggressive landings, a guy needs determine his max desirable attitude with acceptable prop clearance.

All this is said in agreement with Drew and Waiter and others about there being little margin for error at the slow end. And to step back another ten paces- other than practicing the slow landings, I seldom take advantage of the benefits of the TE Fences because more often than not I add ten mph to my approach and touchdown speed. On takeoff I normally let the bird lift off when it is ready and accelerate to 150 mph to climb. Bottom line, energy is our friend.

But Marc your interest is to land slower. Or maybe to install high lift devices. I probably won't be able to stay away from that thought either...
Hope you get more good info and that your short landing pursuit here gets you what you want.

You mentioned Micro vortex generator’s claim of 9 knots reduction, and if it was real, lots more folks would have them installed. I am wondering how often when someone gets the vgs on their EZ, they have some fun and success, and good capability if and when they need it. And thus satisfied, thereafter are somewhat leery of the very bottom left corner of the flight envelope. As on most airplanes.

If and when you are fortunate enough to get a chance, like i did, let someone who knows how to fly the airplane show you short field landings in a stock 0-235 LongEZ. Maybe you are that guy, to show someone else.

Oh yes... on lowering stall speed? For real?
Some might say the following solution is free, or even saves cost...
Others might say it “costs too much”...
An airplane always stalls at the same angle, with higher weight causing higher stall speed, lower weight allowing a lower stall speed. A sure-fire stall speed improvement... reduce weight : )

Good flying- and landings,
Bill James, Fort Worth VariEze

Providence

2007-12-24T13:45:00.001-08:00

Is there a spiritual component woven into the tapestry along this Eze life?

Probably the main thing that has fostered success with the plane thus far is having no expectation that an airplane would make me happy.

Flying things had been part of fun stuff since I can remember. They say time spent flying isn’t deducted from one’s life span. I hope the hours count that this kid spent careening in a rope-suspended apple crate hanging and banging around that spectacular pecan tree in our back yard.
A silver bullet shaped Commando Cody helmet allowed an extra 5 knots on the soup can lid airspeed indicator. The helmet bag was a long skinny box that said ‘Reynolds Aluminum-75 feet’ and the helmet had to be reshaped before and after every donning.
A Commando Cody Rocket Backpack provided more mobile flights around the neighborhood - a couple of 2x4 lumber rockets with 5 point harness, my father's old belts nailed on. Matching setup for my dog Lady. Yes we turned heads.

How Big A Deal Is This
There are moments, points in our life where we could have asked ourselves “How big of a deal is this?” Looking back we would recognize significant benchmarks.
For a four year old the world can be a pretty confusing place. I can almost remember the childhood moment when a big decision had to be made. It was on whether to be happy or not.

From my earliest remembrances there were folks that liked what I did and others that didn’t like what I did, even when it was the same thing. So on that one big day, it was up to me to decide how things were going, and most importantly how I felt about it.
I made a simple decision. “I’m happy”. It stuck. Not that everything was easy after that, just settled. Was that a big deal?

Also at about the age of four I remember feeling the warm spiritual cloak that Someone put around me. I still know and feel that comforting support. One day it got put into words for me. I was watching TV. It had a round grey fuzzy picture. Art Linkletter asked a little boy, “Johnny, if you could talk to God, what would you say?” The way I remember it, the boy thought and looked up and said, “Hi God, this is Johnny- Count Me In!”

Little Johnny’s nutshell response hit my nail right on the head. While there are plenty of spiritual rabbits to chase, "count me in" is today my simple response to the Maker Of The Molecules.
**********
“A guy is about as happy as he decides to be” has several supposed authors including Abraham Lincoln and Mark Twain. But the sentiment and substance was part of my temperament and evolution even before I heard it.

The airplane is a major component opening up a wild aeronautical ride chasing air molecules along sleek cowl lines and ragged rock ridge lines. But it wasn’t expected to be the actual vehicle of happiness.

Building Blocks
After Marine flight school, we’d been in Hawaii a couple of months. A pastor named Paul came by to visit. We had visited his church. He asked if I was a Christian. I said I did believe in Jesus, but did not believe in myself. I told him there had been a little water under the bridge since I last felt very spiritual.
Through high school and college sports I had become prolific in the fine art of ribald communicative device. Of course colorful cursing was the common ready room lingo of us pilots, always at the ready with the manly quip. I didn’t even have to think to spout a real humdinger. In fact, phrases could slip out uncontrollably and this had become somewhat of a problem in polite company.

In quiet moments I would often hear my mother’s knowing voice with her uncomforting admonition that vulgarity was a verbal crutch for a weak man. A spirited high school English teacher for 44 years, with her natural wit and rubbing shoulders with Shakespeare and friends, she had no problem getting her point across. Her firm intellectual slice and dice set many a teen age boy on his heels and on the right track. I had observed her evaluations of off color parlance to be accurate, and this uncomfortable reality framed my response to the pastor’s spiritual question. I told him I totally believed in Jesus, but I just didn’t feel like a Christian.
He described a man in a canoe pushing off from the shore to go fishing. A little later he looked back and was so far from shore that he couldn’t get back. In fact, it looked so far back to shore that it seemed he had never even been there. In a spiritual sense, as hard as he might struggle, he couldn’t get himself back. Maybe like me. Maybe I wanted to get back but just couldn’t overcome the vast gulf. The pastor said I was right, I couldn’t do it. But, he said, God can. He can reach through the separated distance and bring me back home. We prayed. I felt and recognized the warm cloak again; and began to know more about that comforting Someone from my childhood.

Six weeks later, in eight helos at daybreak we thundered across deep spiked green mountains and out over the blue Pacific waters, transporting Marine troops to Molokai. We were caught in the sun’s exploding grandeur. The early preflight and multi-ship takeoff had been hectic. Catching my breath, I looked out over the vast blue ocean and into the reflected blazing sunrise.

I was just realizing that this was probably the most spectacular work of nature and art I had ever seen. It caught me and pulled me up and up and in. In my spirit, a whole new world opened up. Overwhelmed, tears filled my eyes. This moment had started when I was about four years old, had gotten a new grip on me at about fourteen, and now again. I hadn’t known it but It had taken hold of me good this time.
In the wild expanse of the moment, I realized I was in the midst of a personal miracle. After years of struggling to control distasteful dialect, in six weeks, I hadn’t even thought of my all too common vulnacular since the pastor’s visit. Not a single word had even entered my brain. For years I couldn’t conquer it. But He could. And did. In vanquishing my harsh habit, He showed a simple, powerful truth in a way I understood; that with Him I could be free.

So, was it a big deal that Paul, the pastor, stopped by? He was one of the most spectacular people I have known. He was a highly recognized author. Among other things, he was my best friend until his death at age 44. That’s when I began to understand that God’s best for us might not be here on earth.

Another milestone.
John was a seminary student that I had hired. He stopped painting the cabinet and turned to me and said, “I am disappointed in you Mr. James, you are out of God’s Will. You went to seminary and you aren’t pastoring a church and you have obviously missed your calling. You are wasting your life.”

By that time in my life, I understood that he was not questioning me, but himself and his own spiritual future. In the heat of battle, so to speak, without time to think, I responded that I was right in the center of God’s Will. I had done what I knew to do concerning seminary and established a successful business and my wife still talked to me, and all my kids had passed me mentally and financially and spiritually and I have total confidence that I am right now right in the center of God’s Will. A quick mental re-check of this statement held. I didn’t mention it but an image of the fuselage in the garage did flash across my awareness. Even years later, the immediacy and simplicity of that from-the-hip response is comforting, especially since it is true.

By this time John had stopped painting the cabinet again. He said “But you can’t really know God’s Will”.
I said “Yes You Can”.
I told him to get back to painting and I would tell him about my big day at Seminary, one of those days that starting out, you had no idea how big a deal it would be.

How to know and do God’s Will
Dr. Oscar Thompson strode into the classroom. He heard the two seminary master’s degree students arguing, one saying that the other had missed God’s Will for not taking a part time position in a church 40 miles away. Dr Thompson looked at them and said,
“Yes, I think this just might be the day to discuss this... How would you like to learn how to know and do God’s Will. It’s easy.”

He had everyone’s attention. We all kinda secretly suspected that you cant really know what God’s Will is.

First he required that everyone agree to his ground rules, that only one person talk at a time. He wanted to hear what each of us had to say. And second, no one would leave the room before he announced the class over, stomping out of class in righteous indignation. He had obviously done this before.

So to the board with a flourish he wrote:
Step 1. Be transformed.
For the next ten minutes he explained that accepting Jesus Christ as your Savior starts a lot of things in motion that happens to us. You don’t do any of it, and you really don’t recognize or appreciate what has happened in you.
Along the way he quoted Romans 12:2 ...”And do not be conformed to this world, but be transformed by the renewing of your mind, so that you may prove what the will of God is, that which is good and acceptable and perfect”.

“So, step one, be transformed. You are born again and Christ’s mind is in you.” Then he wrote:

Step 2. Do what you want to do.

He turned around to the class and smiled. The protestations didn’t take long. The first student stood and said,

“I can’t do what I want to do. I have to do what GOD wants me to do!”

Things unraveled as you would expect. Some would have stomped out if not for the pre-agreement. After a few moments Dr. Thompson called for order. He had everyone let go of each other’s throats and sit back down. For a few minutes he listened to each person’s thoughts.

He added that “Step 2. Do What You Want To Do” had a Part B, which is to consider your options wisely. Some things are just not legitimate options.

He worked through the parable of the talents in Matthew 25, and the shrewd steward in Luke 16. I thought the steward was being underhanded and hadn’t previously expected he was actually using his own commission to earn positions of favor, and was a little surprised to hear Jesus encouraging us to be smarter.

Dr. Thompson ended telling each of us we were absolutely best positioned to know and do God’s Will for ourself.
“Through Jesus you now have the spiritual mind of God and you can read and hear His words even through life’s tumult. He knew you from before the foundations of the world. He wonderfully formed you and prepared you and invested you with talents and interests and passions. Unearth them. Use them.”

“Be transformed, and do what you want to do.”

We knew of Dr. Thompson’s illness and that he was in the last semester of his life here on earth. He went to be with the Lord a few months later. I look forward to catching up with him.
John the cabinet painter? He was excited to think about being able to be in God’s Will and have fun and move forward in life with renewed awareness and appreciation of his God given talents and passions.

The hour with Dr. Thompson that day is relived often. This truth is the foundation of my confident position. He pulled awareness and truths together from my earliest remembrances and tied them to the present and flung and anchored them into the future. It was a spectacular moment in time that I didn’t want to end. Actually it hasn’t.

Was that a big deal? That afternoon in 1980 I went out to Sycamore Airport and dusted off N1761, a 1947 Cessna 120. I had bought the plane after not taking that last flying job. But when starting my master’s degree studies, the plane had been considered a secular frivolity and an inappropriate distraction and waste of time for a student involved in God’s serious work.
Turned out that it was providential for this particular student to move to Fort Worth and complete seminary and then... do what he wanted to do! Crazy.
But that very day the spunky taildragger got going again. Over time and understanding, interests and passions and talents were unearthed and what do you know, a burried dream got going. I didn’t expect it, but work on the VariEze actually went better when the contracting work was busiest. Where all the normal aviation channels had closed to me before, now flying was blossoming open again. I took a customer for an Eze ride and ended up in the Sim at the airlines. And today it gets even crazier than that.

Recently in a group of a dozen fighter types, one asked my ex F-15 cube mate if he was going back to corporate flying. To my surprise he said "No, I'm going to do what Bill did, build my own plane and fly when I want". He now owns a 90% LongEZ.

It is my experience that the Lord wants to give a guy his heart’s desire. Even so, the elements of my spiritual core have not come easily. I would rather that some things were different. For example I think it would have been easier if the Ten Commandments were hard-wired in our main frame noggin from the beginning, rather than this discipline stuff. Oh well.

I chuckle each time I fill out an offering envelope. What’s so funny about that? Years ago we joined our current church about the same time I subscribed to the Canard Pusher newsletter. A while later I noticed that my Eze newsletter ID number and my church envelope number are identical. Ha.
Is that a big deal? A coincidence just between us molecules? But sure is fun. They are framed together on the hangar wall.

Does being born again spiritually make a guy perfect or smart? Probably not. Us humans can do some pretty unconscious things. In fact, because of this I know what I would think right before I die.

What goes through a person’s mind just before you die? I hear that you think of your kids. Or that your life flashes before your eyes. For me, my family passed nodding and smiling across my consciousness and I whispered see you soon. During the last couple of seconds, I wondered to myself out loud whether Jesus was going to harass me about getting into this predicament. That’s what I thought about. When faced with eternity, I was expectant to meet my maker as I was, relying on His grace.

Our middle son was popping the ball up every time at bat. I suggested that he was using all of his muscles in the swing at max power and that they were fighting each other, and that he should relax and watch the ball and let his brain and body do their thing. It worked for him. He has a Palomino League World Series Champions ring the size of a door knob. I told him, and I tell myself, hang in there and do your best.
I ‘hear’ that same advice pretty much every day, spiritually... Stand in there and do your best... Do what you want to do... Abide in Me and all things are possible...

As for the spiritual dimension to flying, you bet. For some reason the sunsets are most vibrant to me right now. Heading out to 17R the visuals open up out to the west. From the distant horizon and deep inside the wonder of the sunset beckons. Finally we are aloft and immersed in the deep blue. We are the center of the universe. At the same time, miniscule, we glide into position among the eons and galaxies of The Maker’s Handiwork. In blazing majesty the Maker of the Molecules flings His flamboyant art gracefully across the heavens, graciously and warmly, including us. Our cozy capsule escorts, and is escorted by the heavenly procession. I love a parade.

As I write this tonight my kids and their kids sit out in the living room. Their spiritual investments come into the conversations as afterthougths. They have certainly passed me...
How big a deal is this.

Merry Christmas! Hope you get everything you want...
Bill James, Fort Worth VariEze

Flying at Peak

2007-10-19T15:26:00.000-07:00

Like all trips to Oshkosh, in its own way, this year was the best.
2007 was the fifth time to fly the VariEze in.
Maybe a dozen total trips to Big O now.
Two main thoughts; spending the first cool evening sitting with Steve Wright in his shared camp ground front yard, and second, flying home at peak.
Including holding on the way up and maneuvering around weather on the way back, the average fuel burn for this Oshkosh trip was 4 gph. Gluttonous compared to some.

The next thought is Schubert and Hertzler’s cooling and drag forum. Kinda like a home team pep-rally with the coaches replaying film of our last winning game. A few great plays, some good plays, some not so good. You definitely feel at home, but you might also take a hit.
Afterward several EZ buddies agreed that it was in fact the best forum ever at Oshkosh, bar none! But there was a non-EZ fellow sitting near me that left in a huff saying “it was a waste of time, they didn’t talk about nothing new”. I think that was the idea, and what made their presentation of such value. As you know, it is available on ez.org.

The trip up to Wisconsin was flown at LOP, lean of peak, throttle wide open and RPM aggressively reduced with mixture. This is now fairly routine after the last two years of testing and tweaking toward optimum efficiency. During that time only one cruise flight was flown at higher power settings, coming back after a hundred dollar fajita, described in the EZ Chron What Flying is Really About. On that trip things were pretty exciting outside and not much time was spent inside the cockpit figuring data. Otherwise, all of the recent flights had the throttle full open with aggressive leaning to low rpms, between 2200 and 2000. So until now I had not looked at max cruise.

You can notice lots of folks talking LOP. Several of the local spam can drivers say they have been doing it for years. Cool. Listening further, it seems they might be talking about something a little different. They are in fact “leaning lean of peak”. However they are first setting RPM with throttle, the normal practice. But there is a difference in flying with the rpm set with throttle and then leaning LOP, versus putting the throttle wide open and then reducing rpm to 2000 with mixture. Not earth shattering. But interestingly preferable if one can do it. Probably could use a better term for the more aggressive leaning practice.

Enjoying the Chase
Life's good when you have something interesting and not too profound that you might go to sleep thinking about and wake up early thinking about, and can’t wait to get busy on.
In the early Eze years it was great fun just getting all the airplane ducks in a row at the same time. Then cooling became an opportunity. Recent years my attention gravitated to the intake limitations and challenges, now pretty well proven and a very good thing.
So now the hunt has evolved to another interesting element of efficiency that I first paid attention to during the 1986 Voyager flight. Probably everyone knows this and totally uses it to fly their planes but me.

Anyway, with all the variables, they flew Voyager for nine days aggressively holding one constant angle of attack. To hold that specific AOA they initially flew at 130 kts using full power on both engines. They reduced power over time, finally slowing down to 90 knots using partial power on one engine. They landed with 12 gallons of fuel.

Based on his record setting flights, I am assuming Hertzler’s best AOA is at some point attained at around 2200 rpm. But I know little about why that rpm was selected or how much attention he or others pay this AOA aerodynamic element on our short flights.

On the non stop 1400 mile flight to Reno, my main shade tree focus was basically finding the cruise speed with the lowest rpm with the least speed loss. Preparing for the flight, reducing the 0-235 cruise rpm at 50 rpm increments, below 2400 there was a significant sag in attitude and speed. 2400 it was. Looks like I had 200 rpm more drag than Hertzler.
The attitude sag was as close as I got to considering AOA back then. The 1400 miles were made with no problem with over an hour’s fuel remaining. If making the trip again, now the intriguing challenge of best AOA would at least be on my mind. A few more little airflow molecules to go out and chase!

Flying Home At Peak
Maybe the AOA thing created a temporary distraction from LOP and is partly responsible for the great trip home from Oshkosh. Leveling at 10.5K my finger habitually started to curl back the mixture lever. But curiosity crept in. With the throttle open the mixture was adjusted to peak for a change. Starting building the plane late and with some interim delays, I have a lot of my share of fuel to burn to catch up with you guys. There was plenty of fuel on board and average fuel burn so far was below 4 gph. So why not just let the steed open up.

She opened up. WOT and leaned to just slightly below peak, after 5 minutes, then 10 minutes, then 30 minutes, the TAS was holding over 220 mph. Up over 5 gph here but who cares. Adding to the fun, the CHTs were aligned at 360 and the oil temp was about 195 degrees. The CHTs also match wide open down at 2000 feet, but not in all other situations.

Hertzler had projected his prop would result in 221 mph and 2700 rpm with my setup. At just over 2600 rpm here, I still have some filleting and finessing to do.

Schubert’s always asking the question - what have all the changes wrought? Well, I got a pretty good indication today. In eleven years, with lower temps and better fuel burn, flight in this regime has gone from about 185 mph to over 220. That’s about all I know for now Terry : )

But like running wide open at 2000 feet on a hundred degree day, max speed up there is not something one will need to do very often. Unless you are in a group headed for that $100 burger. Then that’s all that matters.

Anyway, the chase is fun. And as usual the point has changed some. The previous cooling goal with the 0-235 was simple... the ability to run wide open at 2000 feet on a 100 degree day with good cylinder and oil cooling. While relatively few folks can probably do that, or even need to, you feel pretty good about having accomplished it.

The other part of the hot day goal, unlimited climb at full power, was and is very practical. And its great fun in a group not to be temperature limited. But at altitude, specifically at LOP reduced rpm, the requirements are less and optimization here may lead to different shapes or components.

This time around with the 0-290, the cylinder cooling was good from day one. But with oil cooling, planning on a couple of upcoming trips, rather than messing with the wide open hot low level 2000’ goal as with the 0-235, the criteria became cruise climb to 12K with the oil temp under 216. You smarter folks have skipped the more stringent low level stuff that I played with and just did this cruise stuff in the first place. Good for you.

So flying home at peak was one fun part of Oshkosh 2007. Other thoughts to come.
While waiting out the weather in Oklahoma, it dawned on me that a significant long term goal has been met, and then some. Because of an early bureaucratic interlude, another story, there has been a respectful but subversive intent to achieve cruise at 210 mph or 181 knots. That means 12 inch N numbers. However, the criteria is actually normal cruise above 180 knots, not max cruise. And knots, not mph. And good news, normal cruise on my plane has been empirically determined to be 179 knots. The three inch numbers are OK.

For now. Schubert and Hertzler, we’re counting on you to finally come up with something new!
Bill James, Fort Worth VariEze

Leaning

2007-09-21T07:54:00.000-07:00

Allen, following your ez.org Hanger Talk note “Temps for the O-320 160hp”

You mentioned leaning in your thread. For the last couple of years I have flown what could be called extreme LOP. My VariEze can be flown with the throttle full open and the RPM reduced with mixture, down to around 2000 RPM. With the previous stock oil sump induction the lowest comfortable RPM with wide open throttle was about 2350, about normal I hear. I am not at all suggesting anyone needs to cruise at 2000 RPM, but rather per your comment, am offering some elemental thoughts on leaning during this experience. You proabably have more info than you can use. The simple intent is to mention some personal experience and sources. Satisfying curiosity and resolving the unknowns and concerns, they can be shelved and we can go fly.

Like you, my early guidance on leaning was to reduce the mixture until the engine roughens, then richen it up a little. A local engineer brought me a stack of material that turned out to be Lycoming’s leaning document. Reading it resulted in basically pulling the mixture back until the engine roughened, then richen it up a little. Unquote.
Beyond that, opinions were mostly conflicting. You could hear snips about running lean of peak, but consistent guidance was scarce, or so I though. The conflicting opinions and old wives tales prevented me from getting too far away from the basics. I had bigger fish to fry and should point out that the plane flew fine during those years of normal leaning.

You have heard about leaning before takeoff from a mountain airport. Not doing so usually results in running off the end of the runway or trimming a few TV antennas and chimneys. At times we have to do that here at 700 feet agl. On a 106 degree day the density altitude can be around 4000 feet. Taking off with the mixture full rich is like having the lawn mower choke on, with the engine staggering. Point is, basic leaning to peak for best power is appropriate at any point. Proper leaning during taxi should also be part of our education. And then use the checklist on before takeoff....

As you can see in the below referenced article, there was more than adequate leaning documentation available in the WWII pre jet era. Running LOP was specifically prescribed for better fuel efficiency, cleaner operation, cooler cylinder temps and longer engine life. Early airline competition was fierce and those guys had to know and do the best procedures. You have probably also heard of Lindberg spending time with P-38 pilots, and that his instruction on proper leaning enabled them to extend engine life and dramatically improve their range and operational capabilities.

This link, http://www.taturbo.com/future.html builds on comprehensive data from the peak of the piston aircraft engine era. It defines terms. It is particularly interesting and enjoyable to me because it mentions the mystical intermediate or follow-through step that I had previously discovered in my plane. After leaning and initially loosing some RPM, you can get back the power you thought you lost. Similarly, when digging for the good stuff in prop data, I was told to go to German engineering data from the late 1930s.

This article and others like it are the good stuff from the pros, where a guy can get basics or dig as deep as wanted. Using best practices on his engine, a guy may match the better designs. As I mentioned before, hopefully you will get to fly with or at least be around operators that practice and teach using the age old proven procedures rather than just running though all the urban legends. Responses to your note prove a wealth of experience is readily at hand.

Talking about leaning with other Eze pilots is interesting. We have a vast breadth of operational extremes. Commenting on my 1400 mile nonstop flight, a number of pilots have mentioned that they don’t routinely lean at all, and had never tried to fly more than 300 miles without refueling. I think their chosen operational level is fine and envy them because with a basic Eze they can live their lives and see and do everything they want right in their back yard.
That 1400 mile flight was flown “normally”. RPM was reduced with throttle and then mixture leaned to roughness and pushed up a little. Probably the main element in completing that trip was crudely determining when reducing the RPM where the largest airspeed loss occurred and cruising right above that speed. The trip was made at 2400 RPM. I still incorrectly believed that the valves could burn up if the engine was leaned too aggressively. My experience has shown different. Reducing the mixture above 8000 feet, the RPM and temps just reduce until finally there isn’t enough fuel for combustion.
Now, being a lot more experienced and having heard more about maintaining a specific angle of attack for best distance efficiency, I have a lot more to screw up.

Along the way I started to learn about a more aggressive LOP condition that made sense. Leave the throttle full open for better air flow through this Lycoming ‘air pump’. Then reduce the RPM with mixture. More potential for efficiency. However, because of significant differences in fuel delivery to the cylinders on some engines, -lots of fuel to one cylinder and not much to another - before the mixture could be reduced enough for much efficiency to be gained, the engine would be running too rough for most folk’s comfort level.

As I heard it, the limiting element causing poor induction with the Lycoming was that the oil pan has a short three or four inch vertical run from the carb before it split into four tubes in the spider. Besides the short mixture run, the carb jet shoots to one side. Thus there is very uneven mixture distribution. At peak and above, the engines run smoothly. But overall fuel burn is high. As the mixture is reduced, fuel levels and power from each cylinder becomes noticeably uneven, temps are different and the engine roughens. Looking back it’s easy to see why some spam can pilots could so readily move on from this effort to lean aggressively.

So. What is a guy to do with the imperfect design? The WWII and airline training on leaning used engineering data to determine the optimal operation for a particular engine. So by just doing a little of that pilot stuff, we have the option to do the same and get better performance without designing our own engine.

So how about getting balanced mixture? That’s another subject, that I have been flying through for the last two years. My intent here was to offer up some basic thoughts and experiences on normal leaning with an intake like yours. Some have successfully extended their intake run and improved mixture distribution. Am sure you are familiar with Gary Hertzler’s setup which uses a tube through the oil sump for a longer mixture run before splitting at the spider. At Oshkosh he was on the third leg of a trip still using the original fuel load. Joe Person mentioned Gary staying over with him and watching him flight plan at 2.5 gallons an hour.

We are in a time period where there is enough proof in some of the puddings to make things interesting. We hear a lot about fuel injection. Because his throttle body is so efficient, I asked Hertzler if the TB is better, or FI. He said that FI would ideally be the best.
For balance, I feel obligated to throw in my opinion of the best thing to have on the plane – Bug Guts! Very few things produce benefit that is worth grounding a flying plane. I recently came across something from the ‘80s in the ez.org CP link I think, on leaning, about RAF considering making a 24 hour flight in their new stock LongEZ.

There is potential for problems. The main caution we hear is “Do LOP leaning only above 8000 feet density altitude because there you can only produce 75% power and can’t hurt the engine”. OK, that doesn’t cramp my style too much. However, in the simple interest of accuracy, after re-reading the references quoted herein, and others, I am beginning to understand how useful using EGT can be at any altitude.

A friend has a powerful twin that he has pampered since new, sparing no effort or expense in maintaining it to the highest level. He went to the Advanced Pilot Seminars in Ada, OK and described his concern and mental conversion the first time they took off and immediately started leaning. Very scary for him, but now he has been there and done that and is confident with better procedures. I haven’t been there myself but have benefited from studying this presentation on their site. Advanced Pilot Seminars, Ada, OK http://www.advancedpilot.com/downloads/targetegt.pps#304,3,Slide 1

For a guy totally focused on getting his engine to TBO, his stress level would probably benefit from having watched the Cessna 150s at a local country airport here over the last 30 years that consistently made TBO. They monitored one cylinder CHT and were flown/abused mostly by very creative novices.

So with my previous 0-235, it was lean to roughness then richened a little. I could have certainly pursued further education, for sure using the “30F to 50F degrees below peak” mentioned in the referenced Back to the Future article. Bottom line, our engines are great. Even if the induction design is imperfect, if a guy gets up to speed on leaning with his setup, he is sure to get much more out of the plane. Hope this summary helps in your operational efficiency hunt. Mainly to get to simple useful practices from the references.

My plane now has a significantly different induction system, another subject. The sunset runs over the last couple of years have included fairly extreme LOP operations evaluating efficiency potential. Curiosity has me looking forward to making the Reno trip nonstop again with the 0-290. Hopefully Tim LoDolce is saving room for my cot in his kitchen.
Coming back from Oshkosh this year, for something totally different, the plane was flown with everything pretty much at peak. -First trip doing this.
Looking at the big picture, since the first Jackpot RACE in ’97 the plane has gained over 30 mph at a lower fuel flow with lower and more balanced temps. While certainly not required for the great Eze life, I would guess more balanced mixtures are a good thing.

Good flying
Bill James, Fort Worth VariEze

Delayed Intelligence

2007-06-30T18:15:00.000-07:00

Finally rolling her out of the hangar!
This Sunday afternoon in-depth preflight ends with everything good and buttoned up. I’m thinking it has been three maybe four weeks since flying the sunset, but opening the logbook later will show five weeks. The flight windows are narrowed by snow on Easter, consistent rains especially on weekends, visits to kids and grandkids... no complaints but time is flying and now I finally will too.

Rolling her out toward the open hangar doors, another mental recheck leaves me squinting and figuring trying to convince myself that I did totally tighten that primer fitting several days ago. OK, I’ll do this stuff right...

Three minutes later, after a quick look-see the cowl is back on and she’s glinting out in the sunlight. I knew the fitting was tightened, I just like to stay in good practice taking the cowls off.

The preflight begins with inserting the brake pin through the strut into the brake disc and setting the nose down. The cockpit check ends with pulling the two nose pins back through the instrument panel releasing the nose hatch. Kneeling down over the nose, after lifting the duct-taped lead-shot-filled inner tube ground ballasts out of the nose its easy to reach in and pull on the rudder pedals to check how the brakes feel. You can watch the rudders at the same time.

The fuel sample shows clear even with all the high humidity. Earlier, the prop had needed only a little re-torquing. All’s good. Let’s light ‘er up.

Pulling the prop through during the walk around produces a quiet hissing inside the cowl. Listening through several more pulls has me thinking a sleepy exhaust valve. It has been a while since the last flight. During the actual start a few minutes later, the hiss goes silent on the 6th pull and she starts on the 12th. A grain of carbon in the valve seat? I expect the idle to be rough at first but it smoothes right down. The engine shows no further issues.

Taxiing out there is a low electric growl in the headset. Now what. Turning things off and on has no effect. Squelching the radio just increases the low growl. Shucks. Guess we're headin back to the hangar. But since we’re out here, why not go ahead and finish the runup. Let's see. Hmmm. The growl kinda matches the engine rpm. Sooo?
Ahah! There is an indicator! The voltmeter shows only 12 volts. Is the alternator asleep? Running up toward 1700 rpm the voltage goes to 13.5 and the growl goes away. Cool! The squelch now has the normal crisp static and a call to Ground is normal. I should quickly claim smarts and talents here. Check list? Yep. Back to the beginning.

During takeoff the pilot stuff settles back to average. Everything starts out fine. On liftoff the plane accelerates up to only 145 mph. Delayed intelligence is insistently tapping me on the shoulder and finally waves a density altitude flag in front of my brain. Even though we are at 700 msl, winter is over. Unlike the cool flights, the temperature and density altitude is high enough to make a difference. The mixture lever comes back gently from full rich and the rush of the wind noise rises to the accustomed 160 mph lifting out over the departure end numbers. Thus mildly reminded, I won’t miss leaning to max RPM/CHT on runup again.

On crosswind the tower beats me to the switch and clears Eze Bravo Juliet for two circuits around the grass strip pattern. They remember. Turning crosswind on the second low pass they pre-approve a west departure. Good guys in there.

Zipping toward the sunset the CHTs settle. On takeoff and climbout they peaked and held around 390 degrees during the high power grass strip runs. On climbout to the west they lower to the normal high cruise temps in a 320 to 360 spread. Pulling to lean of peak the airplane settles in to an easy lope and cruise climbing at 150 mph the CHTs settle in from 290 to 340 degrees. An earlier reshaping of the upper NACA lip to a better inverted airfoil shape lowered the temps on that side about 40 degrees.

The oil temp is settling from 205 and will hold at about 195. In level flight the elevator trailing edges are about an eighth inch higher now with the 0-290. On less aggressive, more normal flights where the power is pulled back early for a more sedate climbout and cruise, the oil temp often stays around 190 with the temps around 320.

Accustomed to the robust takeoff and comfortable cruise conditions, only now sitting here at the keyboard does the different intake and carb setup come to mind. I’m so glad.

Heading back in toward home a glance back at the fuel gauges shows the sky darkening toward the auburn sunset. Without much help the plane turns 45 degrees for a better view over my shoulder. After a dozen wingovers, surely we belong to each other forever. After a minute or so we turn back on course. Out ahead lights begin to twinkle in to the warm shadows of summer dusk. The pilot stuff is coming easy now. I don’t want to stop. Rolling level on the 45 degree entry for 17R things are fast and good and I’m ahead again. Scanning outside for traffic, hands move easily on the controls.

It is good to get up to speed again. I'm thinking that it was a recent AOPA article that quoted a wise pilot's observation that everyone makes mistakes, the difference being whether attitude and discipline have provided any margin, or not.

Planning the approach includes the summer regime sinking in. When I put her to bed she won’t need the drop light in the cowl overnight to kill the chill anymore. It’ll be fine in the mornings now. Flying will be a little different. Lots more bug guts. Thinner air means a little less oomph. Afternoon thunderstorms.

The brisk turn to downwind triggers the ritual to check the gear down three times. Be ready to dance the rudders a little.
Rolling smooth through the 90, can’t help but eagerly anticipate a greaser in the slightly bustling winds. Sometimes a guy gets to do a little of that pilot stuff, thank goodness.
Is there another feeling like gliding her in and massaging her down through ground effect and chirping the tires and rolling out easily nose still high in the landing posture and gently settling her smoothly level just at the right time, everything good, just like a guy knew what he was doing.

Coasting up to the hulking tin cave, “Cheated Death Again!” is announced to bounce out between the hangars. Mixture slowly back and the last wisps of hollow thunder escape out the exhaust. She rolls into place and glides to a stop. Everything is still. Echoing silence. Punching the switches off, I stop. I don’t want to move yet. Slightly tired. A good tired. Somehow more invigorated.
Still a pilot for moment longer, grin into the ritual push up and out, sitting on the longeron, turning back to see the cowl and prop still there. That’s always nice. And as always an appreciative glance at the intakes on the spar. Thanks guys.

I don’t know what occupies the mind of lots of folks these days during a sunset...
Thank goodness.
Bill James, Fort Worth VariEze

What Flying Is Really All About

2007-03-20T19:51:00.000-07:00

More Power!
OK, OK, I’m caught up in muscle madness a little. The horsepower is piled on and the lean of peak glide ‘n slide is postponed for a while. And pass some of that nitrous around while you’re at it.

A contingent of the Texas EZ bunch is saddling up and preparing to leave the Lufkin County hundred dollar fajita brunch. The local folks ask for a flyby, or two. Lead’s brief leaves room for more. By the fifth or sixth circuit around the pattern the adrenalin is cranked up pretty high. Too soon we peel off to the north for home.

Rather than the milquetoast weekend fliers that arrived a couple of hours earlier led by Dash 5 in the slowest plane, we are now raucous white knights racing skyward with canarded lances piercing the crisp air in focused search of any dragons left to slay and any windmills needing to be jousted.

Leveling at cruise altitude we wordlessly form the valiant V, still giving no quarter to each other or the distant fuel pump back home waiting to suck up the credit card. Dash 3 zooms from below rolling up and over into a nice position off my right wing. That is a sight to behold. Even if anyone in the flight was foolish enough to ask, no one is likely in the mood to back off a hundred rpm.

Finally pacing Lead, I move in on his right and jokingly complain about having to slow down to fit in. Evidently Lead doesn’t see the humor. He is pulling away and I am caught in the sag, having to grit my teeth and tighten my stomach a little in catching up.

Enjoying this rush of the run home, I’m thinking of the much more sedate trip down earlier this morning, paced to the slowest plane. I am extremely glad not to have that distinction. As we hurtle along Dash 3 must be thinking along the same lines. He says, “I guess we’re not waiting for Dash 5...”

I think of the almost finished EZ Chronicle back home on the efficiency of the Long EZ and how it is a more practical airplane than my favorite subject the Varieze. I shake my head in mild self-criticism for now being caught up here in this raucous romp. And I grin. What a country. The thought wells up again...how can all those people stand to be down there on the ground and not up here doing this?

I hold on to the moment, marveling at the sleek skimming porpoises smoothly rushing and rising and positioning, pulling out far ahead of the workaday world chasing us from down below. Those around me are, in a sense, warriors. I know their stories. I know their diversity and their work ethic. I know their determination, how they fight the daily battle of life and mostly win, winning enough to grasp for their very particular brass ring.

We thunder along in the too rare atmosphere of free flight. I think that this is a high point of our life skirmish - of discipline and productivity in the battle for freedom to be fought and won here at home. I humorously imagine proudly rising to solemnly pledge allegiance along with hordes of patriotic muscle car massagers and Titleist bashers and Harley drivers and dirt track racers and struggling enthusiasts of every shade and brand.

Tongue-in-cheek I mouth a pledge to continue my part in upholding the struggle for the rights of freedom and hamburger fly-in loving mortals in this great country, as we work and produce and win and loose and get up and go again, pursuing and living the American Dream. But saying it, I realize how much I mean it. Scanning outside, the view is of blue skies and white clouds mirrored in shimmering blue lakes, the very embodiment of alluring travel commercials. And inside, snapshots of my Canard Pusher dreams - a woven instrument panel, a Brock control knob, the special instrument that I had so long hoped would someday come alive...

And that Oshkosh moment. There was a pretty good crowd around the VariEze. A man asked me how far the plane could fly. I pulled out the marked-up US map and showed him the tracks of flights radiating out across the country from Fort Worth. Another man elbowed up and asked with an accent, “Who give you permission to fly all dese places?”

In the silent moment that followed, I guess many of us in the crowd came up with our own answer. I grinned and said, “I give myself permission to fly. This is America! ” And then explained a little about our air system. But there is so much more to our country’s greatness. I look out and squint a little and can almost see the bearers of our freedom through the ages…

But everywhere I look the image of a picture from a few weeks ago haunts me. A hand written sign in a sandy US Marine outpost says,“America is not at war. The Marine Corps is at war. America is at the mall.”

I remember in 1991 talking with a Fort Worth Marine recruiter. They were going to war flying Helos that still had my sweat in them. He said thanks but no thanks, and that they were getting calls like mine from all over the country from other former Marines volunteering to go back in.

I didn’t call them this go-round. Many of the CH-46s over there today got their baptism of fire in my era. This week there are several less. Sitting up here today, I know there is no free launch. I think of the true heroes, far distant, fighting my war, fighting for my kids, fighting to live, fighting to protect their family’s way of life here, paying the high price of things we take for granted, the things they long to get back home to.

This time cruising aloft here includes another prayer for our Patriots fighting this war, pretty much alone. I doubt that they know the width and breadth and depth of their support back here from comrades in arms, although many are finding ways to show our support.

I started building the plane on a nickel budget and got to liking the minimalist approach. I tend think a lot about simple efficiency. But not today, not right now. Pour on the coals. I look around at my fellow EZ travelers and relish the freedom of my spectacularly providential birthright to earn the ability to do something pretty spectacular in a pretty demanding arena in my own pretty small world. Every day as my kids and their kids get home safely, I thank God for those here and those far away from our country, standing almost alone, but standing firm.

It has been said that, one way or another, flying is about money.

No, Flying Is About Freedom.

Bill James, Fort Worth VariEze
EAA # 104225, Member since January 1975

LongEZ, A More Practical Airplane

2007-03-20T19:13:00.000-07:00

Long-EZ, a more practical airplane
Heading out for Rough River, one north Texas Long-EZ lifts off an hour before the rest of us. Even with the other EZ's head start, James Redmond in his Berkut will still be the first to call entering Rough River.

I lift off from my far southwest edge of the DFW Class B while the others are swarming together in the northeast quadrant. They have lifted off a little early and are already 15 minutes east of Dallas.

While James Redmond is up at 14K, we are cruising at 7500 feet and all getting about the same minor tail wind. The group includes a couple of detailed Longs, Vance Atkinson’s Oshkosh Grand Champion Cozy, and Scott Carter’s Wright Brothers (or is it Lindberg winner?) award winning Long-EZ. They are all playing dueling wing levelers and fuel flows and make more than a few pointed mentions of their bountiful and important cargos.

I lean back and relax listening in to the juking and jousting, again enjoying this high slice of EZ life. During the trip they stay pretty much together and I catch up to them a little and have time to consider the relative pecking order and status of the group. Can’t help it. Of course i get to make the rules.

Things settle into a rhythm and every few minutes they report general comparisons on ground speed and fuel burn. The ground speed settles to about 180 knots. An initial fuel burn roll-call starts with a distracted 11.2 gph. Vance counters with his 7.8 gph and causes everyone else to sit up and get leaned out. The 11.2 gph’er quickly tweaks down to 8. At this low altitude and still under 6 gph I count my blessings and continue to consider elements I gain or concede.

So far, in ten years I have been too busy to look up and covet what I might have missed by choosing the VariEze, and have never wished to be in any other plane. But cruising along and listening in on how everyone else is doing, you can’t help but notice the upper range of capability and the overall outright stunning performance that these guys are getting.

These trips are always a big event to me. If you are traveling to be with other EZ folks, it’s certainly nice to get started early along the way. It was a great day back in the Marines when a couple-a-few or a dozen helos headed out on a mission roaring through tactical troop inserts on one island, then regroup and shut down on a nearby beach for lunch, or maybe refuel at Maui and hurting yourself at the resort hotel buffet. After transitioning to the Cessna 120 civilian world it was quickly obvious that having a mission and mixing with others was more fun than just boring holes in the air.

And in Texas, flying or driving, anytime I get home from another state in half a day it is a big deal. On family trips to south Texas we routinely drive twelve hours. Someone recently demonstrated to me how you can flip Texas to the left and put Houston in the water off LA, or right and put El Paso in the Atlantic. Or flip the state up and South Padre Island is a stones throw from Canada. With the versatility of the plane I look forward to claiming more parts of the country as friends. The VariEze has certainly allowed significant widening of these personal horizons. I can’t help but think how crossing the country in this way would astound the Wright Brothers, or Glen Curtiss. Can you believe those other folks don’t even look up when a plane flies over?

So how did my pecking order turn out?
Everyone made it to Rough River. And back. Each in the style and comfort and in the flight accommodations that they chose. Extreme personal freedom, how ever you choose to describe it.

The group pecking order? One to ten?

All Ones.

Although cruising strong in a very sweet ride, being around the LongEZs I can’t help but notice their strong points.
Did you know that a number of VariEze guys have a 90%/90% Long-EZ lurking somewhere in a hangar back corner?

More Practical
To the point, I readily agree that the Long-EZ is a more practical airplane. It started as a modification to resolve significant limits in VariEze payload and low-speed handling. I remember seeing a picture of the first LongEZ with VariEze wings a wider spar, and then another with a completely new wing.

With one-third more wing area, it readily handles a starter and alternator, normally has a lower landing speed, is generally more capable, and just allows for a more civilized lifestyle all around.

Walking the flight line among the 102 canards at Burt’s birthday a few years ago he was asking “What are all these VariEzes doing here, didn’t they get the message?”

Some folks are surprised that the Long-EZ isn’t necessarily longer. In our hangar my VariEze is longer than the stock Long-EZ in the next slot. I think both designs have the same bulkhead and firewall fuselage stations.

The major differences are the 1/3 more wing area, two inches more front seat shoulder room, and about twice the fuel capacity. The wider strakes and center spar give the Long-EZ front seat elbow room and side baggage room. Long actually refers to range, about 52 versus 26 gallons. One of the Canard Pusher spec sheets mentions that a LE can carry the pilot and 52 gallons, or two people and 38 gallons.

Even though both planes are highly capable and might be able to stagger off the ground with quite a load, overloading a Long-EZ’s 99 square feet of wing area with two new-millennium age folks-plus-necessities is a little less significant than overloading pretty much the same stuff into a VariEze’s 66 square feet of wing area. The Long-EZ is just a more practical airplane.

I’m still watching for the aircraft that doesn’t harbor a hard compromise.
The payload of either plane can be quickly eaten up. A new Long-EZ owner once stopped in at the hangar shaking his head saying he had just weighed his new toy and that with him and his wife two gallons of fuel put them at the advertised gross weight. Another friend tells of his surprise when his LongEZ was topped off with fuel rather than getting the 25 gallons he requested... and the ‘interesting’ ensuing takeoff.

The impression I get from flying both is that they are great handling planes. Once you get acquainted, pitch in both planes is a positive experience. There is definitely a little different in roll in the two planes, but it doesn’t seem to be an issue.

Many airplanes have surprising results when using rudder alone. Comparing the two EZs, the LongEZs I have flown seem to have relatively ‘easier’ or more coordinated turns with less, or even without rudder input. I don’t quantify that as better than the VariEze, just different. I am very pleased with my plane’s handling. Getting up to speed in either plane should include practice with and without rudder, and especially on crosswind approaches reminding oneself to be aware of and ready to use them.

With the rudders, an interesting exercise is to roll left to 30 degrees banked turn, and then over to a right 30 degree banked turn. In LongEZs I have done this without rudder input. A little rudder helped, but wasn’t required. The same maneuver in a VariEze with and without rudder is different. The VariEze is definitely a rudder airplane.

In my VariEze, rolling 30 degrees left to 30 degrees right with rudders is very brisk and comfortable. Without rudder input there is a little hesitation or butt wagging joggle going through wings level. Its my habit to lead turns with a little rudder, especially on landing.

Evidently not all of you have access to the CPs and Burt’s philosophy on the 0-235 Long-EZ. Here it is, from CP 28 Page 5.
How much Power ?
One of the basic functions of the aircraft designer is the sizing of the aircraft such that the selected powerplant is correct. An engine too-small for the aircraft results in inadequate climb in high-altitude summer conditions or an unacceptably long takeoff roll. Too large an engine is wasteful of fuel because either the high cruise speed is at an inefficient flight condition for the airframe (low cruise lift-to-drag ratio), or the engine itself is inefficient when throttled back to obtain the speed for a good lift-to-drag ratio.

If a designer attempts to select an engine for optimum cruise efficiency, ie. at a flight condition for maximum miles-per-gallon he finds the engine inadequate for climb. This situation is not unlike that of the automobile designer who finds his vehicle is cruised at a speed far in excess of that for the best mpg. However, the designer knows that the airplane should not operate at best L/D (or at best mpg) anyway, since this is not practical unless you are setting a distance record. Increases in speed above but near the best mpg speed result in only small losses of mpg. But, as the speed increases considerably above the best mpg condition the mpg drops drastically. The big question, then, is how fast should you really fly? If this question can be answered, then the designer can size the engine for this practical speed.

Aerodynamicist, Dr. B.H. Carson if of the US Naval Academy has published an excellent analysis of the fuel efficiency of light planes (AIAA publication 80-1847) and has presented theoretical rationale for practical cruise efficiency. His interesting technical treatise is beyond the scope of this article, but the summary of findings is of interest to pilots. Rather than focusing on the cost per distance (mpg), he finds the speed that gives the minimum cost per speed. This “cruise optimum” speed corresponds to minimum outlay in extra fuel (over best mpg) per increment in additional speed. This speed corresponds to the closest approach of the airplane to a “technology barrier“ of efficiency proposed by Gabrielli and Von Karman in an article “What price speed?” published in Mechanical Engineering Vol. 72 October 1950.

This “cruise optimum speed, at 32% over the speed for best mpg, results in a 16% increase of total fuel used, requiring a 52% increase of power and saving 24% of flight time. This speed is regarded as the most productive use of excess fuel for cruising. The pilot should consider it his best “economy” cruise speed.

Accepting this theory, lets see what the resultant engine size is for the Long-EZ. At 8000 ft. altitude and 1325 lb. weight the “cruise optimum” speed is 139 kt. (160 mph) and requires 47 thrust horsepower (55 brake horsepower). This is a power setting of less than 48% when using the 118 hp 0-235 Lycoming. This suggests that, for 65% power cruise (to allow operation at lean side of peak EGT), the ideal engine for a Long-EZ would have 86 hp. However, here is where the theory breaks down. The ‘Long’ is a fast aircraft for a fixed pitch prop application. Thus, with the low prop efficiency at slow speeds, it requires a 100 BHP engine for satisfactory take off performance.

The larger engines, 160 BHP for example, are wasteful of fuel at any speed. This is because specific fuel consumption (SFC) increases as the engine’s power is reduced below 75%. (Snip - a related graph is not shown).

If a Long-EZ is cruised at “cruise optimum” speed, its 0-235-L2C engine will burn 8% less fuel than would an 0-320-B at the same speed (48% power for the 0-235 and 36% for the 0-320). If both engines were run at 65% power the 0-320 would burn 22% more fuel than the 0-235 for a given trip.
<<<<<<<<<<< So there. LongEZ 0-235 efficiency from the horse’s mouth.

Munching on this and comparing it to the FLYING HIGH AND FAST (http://www.vansaircraft.com/pdf/hp_limts.pdf) helps point out the fine balance between structural strength and weight versus speed.

So. What is it worth to have the larger planform but having to stuff in more power to keep up with the pack? A 22% loss of efficiency? Not worth it? Or Priceless? I guess that’s your call.

This is not a technical paper on the LongEZ, rather an admiring concession to a few of its noteworthy attributes. I look forward to learning from those of you that have optimized these canard types. If I am around where you are, please be persistent enough to tell me about your successes.

Bill James, Fort Worth VariEze

Nothin’ to that cooling stuff

2006-07-14T18:27:00.000-07:00

The mini Ford GT held my attention. The sleek polished body was made of aluminum I think, almost seamless – was it chrome? When I first saw the car I thought it must belong to the liquid-metal Terminator bad guy. Each day walking by the Oskosh Ford pavilion it pulled me back in for another dream session, going back through the years to being sixteen years old in my two-speed PowerSlide ’52 Chevy imagining someday drifting such a machine as the GT through the hairpin Texas hill country curves. It seems to be a craze now but drifting ain’t that new of an idea.In a documentary on the development of the Ford GT in the ‘60s, the way I heard it, Ford was in the process of buying Ferrari and something went wrong and the enraged Ford decided to beat Ferrari at whatever cost, in their own back yard – the 24 hour Lemans race. The resulting wrap-over doored racer had a brute-force-speed-shaped elegance that lit a fire in many of us.Watching the documentary footage of the huge development effort was interesting but the thing that stuck is that after three years, right in the middle of their intense, no holds barred six year effort, the experts had to go back to the drawing board on the cooling. Ford had them working on the cooling 24/7 for some time, until they got it right. You’d think that those engineers would have quickly done that job up front, and it wouldn’t have been a problem after that. Ha. Not that I related or anything, but seeing the evolution of inlets and scoops was fascinating.Today I am cruising along effortlessly at 8.5K, resting in the cool in the Eze enjoying the speed and the power and the sound and the hill country passing below, intimately speculating just how the airflow is swerving around the lower cowl and exits (I’m surely wrong) as they pull just the right amount of air around the oil sump and through the cowl and can I proclaim it loud enough, through the oil cooler. And remembering just a few days ago when the oil tracks showed the inner cowl air going backwards and out an inlet. One of my prouder days.The new exits are a two-minute adaptation like Cory Bird’s yellow cowl exit vents pictured in the March Sport Aviation article on cooling, also with another look at Mike Arnold’s AR-5 exits. These are basically a square on the lower aft cowl surface, cut on three sides, with the forward lip pushed up into the cowl about ¾ inch, for a 7 degree floor angle to the relative wind.

I thought there might need to be a little surface area aft of the exits and guessed at how much would be best. They are about six inches forward of the aft cowl edge. Those in the Sport Aviation picture have a neat leading edge lip to kick up the air to add to the low pressure, which was quickly added to mine using a curved aluminum spoiler. I still get goose bumps remembering seeing the oil temp gauge smiling 212 degrees and then 202 degrees back at me on that excellent flight where it finally worked. Nothin to it.That night it did occur to me that I should have done whatever I did long ago. Seeing the Ford guys go through iterations of bigger engines and brakes on the GT 40 and then in mid-stream have to go back and redesign the cooling, I sneak a little smile and breathe a deep sigh of relief and remember that if it was easy, …how does that phrase go?I can almost hear builders right now saying to themselves that they did all this long ago and never had any cooling issues anyway. Congrats to those accomplished wizards. I gladly defer to them for technical profundity and mention basic details, as each installation is so different. But I am making notes on ten years of plenum operations hopefully for next time.The time for digging in and making the dream car a reality came and went and I didn’t grab for it. For now I am satisfied with a well-bought simple red Mustang ragtop with black Steve McQueen Bullet rims and matching black parking aid devices ( – don’t dare mention to my wife that they look more like racing stripes) … a car that I have never turned a wrench on. Sitting on the wrong side of having maintained a small fleet of cars and vans for the kids’ soccer practices and college, I gladly rest my auto socket set.Instead of just a passion for cars, the winds of Mojave blew a wisp of fiberglass in through Texas, well, Japan, that moved most of my other childhood fantasies aside; or maybe encompassed and pulled them together. Looking at the foot-long GT 40 on my desk I remember my dad leaning on his old faithful pickup and telling me why he kept his full size truck instead of one of the spiffy new mid-sized trucks -- because at 84 he could still get in it. And I imagine the contortions that would be required to get in that three foot high Ford GT.What Eze back seat sight gauges? What longeron hippityhop?

Gotta remind myself to do my stretches and limber up again tonight. For some convenient reason the Eze isn’t held to the same comfort and maintainability standards that settle on the cars so easily. It is held to its’ own set of standards. Maybe I use a different measure here because it puts us right where the advertisers go to lure us to Oklahoma or Missouri or Hawaii, skimming us low over their best and most beautiful rivers and valleys and mountain crested spectacles – our back yard. I may have started to understand part of the flying bug thing, thinking it probably has something to do with seeing Peter Pan again as an adult and recognizing through that doorway to the past some of the half-remembered, swimming-through-the-air dreams over and over through the years, struggling and jumping and kicking to get off the ground and pushing-off over the telephone poles and trees until finally breast stroking and dog-paddling enough altitude to get that breathtaking free sailing momentum going and then, and then, lofting easily over the cool green countryside – and later in the Eze chasing sunsets, being there again, about as close as a grownup can get…for now having regained some respect and breathing room, at peace and grinning back at my unseen but respected miniscule nemesis contemporaries, the waskely air molecules back there gleefully running the rapids through the inlets and midlets and outlets, running just a little easier now.

Nothin to that cooling stuff. Right.

The Third First Flight

2006-06-09T18:29:00.000-07:00

Getting ready for the Third First-Flight
The summer of 2005 lasted here from April to October. This 100 degree OAT timeframe was scientifically chosen for first flight and engine testing in order to prevent frost from being a safety issue. This note chronicles a few thoughts and reactions to the evolving understanding of how well or not the 0-290 engine installation works, first on ground runs and then in the air.
April 2005The 0-290 now has ten starts and 0.7 ground run time. The new plenums and wraps and such have been step-cured. And now I finally have all the new components on speaking terms – accomplishing mag timing, confirming electronic ignition operation, and getting to know the carb accelerator pump. Pilot starting technique aren’t ever be a problem of course, ha, but am gaining experience. Six of the ten starts have been on the first or second pull. The way it purrs, I may call it Morris or Garfield, or Felix.
Why is this called the Third First Flight?VariEze N95BJ’s first flight back in 1996 was uneventful. That 0-235 and prop had already flown a year and a half on Scott Carter’s LongEZ and was just broken in good. I also had the advantage of three months in the front seat of Nat Puffer’s original VariEze before lifting off in mine for the first time. The airframe was the only unknown. It only needed a small rudder shim to get on the straight and level.
The second-first flight, three years later was with the new untried downdraft plenums. That flight was actually approached with more apprehension than the airplane’s first flight because of the significant unknowns with the unique plenum cooling installation. Ground tests were good but then I somehow had to determine that it would also work at two thousand feet. I was well aware of what over-temping on climb-out could mean. But once in the air the summertime CHT’s were tamed on takeoff roll and then reduced nicely on downwind. It worked. Ha.
This Third First-Flight - with the 0-290 - is upcoming (This was written in summer of 05. It wasn’t yet known that the development period would include a pesky leaking intake valve fouling one cylinder occasionally, and a firing but bad plug).Last night the three friends (mag, E.I. and accelerator pump) let the pilot in a little on their mutual philosophy/conspiracy. In other words, I am getting the hang of how to prime and pump and position the throttle this time of year.
The carb heat temp effectiveness was also tested last night. Ground runs have shown interesting intake cooling activity (condensation on the long, curved intake) so a considerable number of carb heat designs were scuffled through to come up with a robust system. This one feeds from the lower plenum next to the exhaust and travels only a few inches to the intake.
At the suggestion of Terry Schubert, a Radio Shack remote outdoor/indoor temp gauge temp sender was plugged into the gourd / carb intake for an actual temperature measurement, rather than just looking for the engine run-up drop in rpm. At a thousand rpm the carb heat lever was fully opened. I was looking for a 90 F degree increase. The gauge started at 62 degrees and in a few seconds went to 96, and then 119, and then blinked HHH, obviously still climbing. Robust enough.
Overall the throttle and engine response is what I would have expected from a normal intake setup. Scott Carter spent a day helping to trace proper engine operation. There was a hesitancy that he resolved by finding and tightening up one of the intake tube hose clamps. It had been tightened appropriately so someone must have snuck in and loosened it.
Four A&Ps have had their toes in the pie working on or checking the engine along the way. Fresh eyes are good and I like to learn from them. Each has contributed in his own way to accurate installation and adjustment of normal items, as well as sometimes offering comments on the implementation or expectations of the unique components.
Cowl Fire Warning System- At least one other person is installing the engine fire detection loop. I’ll look back in a few years to see if that simple dual wire element was ever used to advantage in the heat of battle.
For liftoff this third time, the alien-like entrails and repositioned elements of this “air pump” will have to orchestrate together in flight. The ground runs have helped to step normally through some areas. Of course I can only totally confirm the mutual cooperation of these creations at 12 K… when up there at 12 K. Oh, and eventually, Jackpot if possible.
May 2005Liftoff.Here we go. Waiting for the afternoon to fly ensures frost won’t be a factor  All items on the pre-first flight checklist are marked off and there’s nothing left to be gained on the ground. Already checked the safety of flight items; the canopy safety catch catches, and the warning system checks good for the nose strut and canopy handle and throttle positions.
Rolling onto 17L there is a slight left crosswind. There is six thousand feet ahead of me and the abort point is generous. Canopy latches have caught the bolts, and it’s locked. Could land back on the runway or the two parallel taxiways, or the cross taxiway; nope no one is on them right now.
Throttle up, good oil and fuel pressure, good rpm, airspeeds moving, half-throttle matches the old acceleration, elevators trimmed ¾ inch TE down, nose lifting at 55, rpms still good, we’re off like a prom dress, good vibrations (none) and the end of the runway coming up at 200 feet and 150 mph, can make a comfortable loft back to the runway from here if needed, turning crosswind into the wind keeps me closer to the centerline for a turn back around if needed, but for now looking good on crosswind here, leveling out downwind, CHTs 400, 405, 390, 410. Oil pressure good,
Holding 140 mph up to 2500 feet. That didn’t take long. Let tower know I’ll be up here a while and level and power back a little for a minute. Winglets and everything still on and cooling inlets look…good I guess; they’re still there. A little nose down trim. CHTs all about 360. Smaller inlets now for the 0-290 and still got about the same CHTs as with the 0-235. (I wont’ know for sure until the chrome cylinders are broken in, but there might be a slight bump-up of CHT temperature, indicating that the inlets might have finally been reduced (from 2x9 each) to about optimum at 1x5 inches each).
Getting the feel of the old steed again, it seems a little weird in a couple of ways maybe, but probably just because I’m paying too much attention. Leave her alone and she’ll be fine. This turn could be better…wonder if I got the same aileron-throw back after the paint job? Hey there she is, liking that rudder. Now I remember - a little rudder makes things nice. I’m the one that needs to be getting up to speed again, not her.
I’m liking it here at 2500 feet. Nice that the sunset has stayed about the same while I’ve been gone. What is that hissing noise? Something’s hissing every few seconds. I don’t even have anything pressurized but it sure is hissing. Let’s see, which of the new items … Hey you’re not going to trick me into loosing track of things here, oil’s good…good pressure but the temp is still rising, no traffic coming over the top here…there’s that hissing again…CHTs good, RPMs, speed, good, no one sneaking up on me, what could be hissing?Everything’s stable now so let’s focus on this hiss. Don’t see any canopy seal flapping and all three catches are in place. OK the last was about four seconds in duration, clear left, there it is again, let’s time it here…about six seconds, I’ve got time to watch it awhile, the plane’s good, just got to keep an eye out for transients up here, everybody likes 2500 feet…there’s the hissing again…four seconds, again, six seconds…What the…Good grief.Hope no one ever finds out that the demons I’ve been chasing up here were vanquished by readjusting the David Clarks a little. Only heard the hissing when looking way around back. I guess the ear seals were not quite as supple after sitting in the locker a while - What a dunce.
Oil temp is not going to come down. Time to hit the showers. One guy entering on downwind on the other side. Let him know I’m descending over here, will probably beat him to calling base. Oil temp will need some attention. Aiming on touching down a third of the way down the runway, coming around nice with a little rudder, right there, settling in just like we knew what we were doing. Set that Eze attitude and… cool, on the ground with no bounce or joggle, hold the nose up here for some drag, cheated death again.
June 05. After thirteen flights now N95BJ has returned to shapely elegance on the ground and in the air. But, she is adroitly evading oil cooling advances with a flip of her winglets. Each short flight is a little longer with more and more room for dalliances and power runs. The upholstery finishes off the new look nicely. The engine intake system continues to act normal. Carb heat temperatures have been normal – good – from the beginnig. Cool.
This always-almost-there pilot has been in sunset withdrawal for some time. But now the much needed airborne therapy is once again salving the ravaging wounds of life. Of course this is part of living the Big Life, right? Whatever, I am again ushering the sleek steed into the hangar after sunset tinged outings, with both of us better for it. The oil temps are still high, but maybe only about as high as everyone else’s in this Texas heat. Still working on getting it down a little, probably with a relocation of the oil cooler. Will probably incorporate it into the lower plenum ducting for some augmented draw from the exhausts. (Did that, worked some but not well enough).
Oil Blow-byI had heard about the possibility of significant oil blow-by in 0-290s from the case vent, and experienced a little of it. Tim LoDolce suggested relocating the case breather vent from near the prop, to the accessory case with the elbow welded into the mag hole cover plate. This was simple and worked. The ‘clear’ case vent tube exits by the exhaust. There is an in line air-oil can that is emptied occasionally.
Along the way the vernatherm operation was confirmed. On the next flight the oil temp stabilized with moderate power. The good cylinder temps continue to allow the engine and my stomach to be comfortable in the 98 degree OAT. After about 45 minutes of this longest yet flight the CHTs were happily observed to make a pretty uniform 35-45 degree reduction. With all the one-after-another delays this was a welcomed advance.
What do they call someone that tries the same thing expecting different results? OK, that title fits, but what about someone that tries half a dozen different things and gets the same inglorious results…Actually, because of past experience and the expected need for robust oil cooling, it was approached in an aggressive manner from the start, hoping to capitalize on earlier oil cooling successes. A lightweight oil sump with internal cooling tubes is used to assist the more traditional components, like the oil cooler. But that still hasn’t been optimized.The previous 0-235 oil cooling finally worked with unlimited full power runs and climbs by enclosing the oil sump and directing a cool air inlet blowing up its aluminum skirt. This lowered summer oil temps about 15 degrees at full throttle. You can see the skirt with the rubber baffling in the Featured Canards section.It is hoped that the internal tubes will also be a helpful addition at some point. I will know more after fiddling with that area some more.
At this point (summer 05) there is little time spent on one distraction. Once normal or acceptable operation in confirmed in that area, it is no longer a squeaky wheel and attention is turned to the next distracter.
Besides the still undetected leaking intake valve and sputtering spark plug, the initial 0-290 flights were thwarted by two inaccurate oil temp gauges in a row. The first gauge read way low, giving a false indication of good temps. Fortunately keeping an eye; actually a hand, on the oil sump caught the inaccuracy. The second gauge indicated 75 degrees high, with flights cut short unnecessarily, mucking up otherwise impeccable troubleshooting prowess and delaying progress. The third gauge now is within 5 degrees of the two test thermometers. Thanks to the author of the article that described how to check the gauges.
The oil cooler location will be moved. Several tweaks have stabilized the temp but didn’t appreciably reduce it. The old girl is back and just needs a little skirt straightening.
>>Summer 06 - Oil cooling is now good even on hot days. Ha. Am selectively removing the little spoilers that had helped to improve airflow in the cowl to see if they are still needed. Stay cool,Bill James, Fort Worth VariEze

A very good day

2006-06-02T18:35:00.000-07:00

Wednesday. This is not just another day. This is a big day. The day I have been working toward for a year. Numerous unfinished versions of this note were started, but stalled without the verdict on oil cooling. Now we have it.

The 0-290 first flight and breakin and the self imposed restricted period have been very deliberate, to say the least. A couple of notes to come on that. There were a few fairly unique engine elements that bore watching, and I watched. The last year has included many pattern flights as the components were evaluated, often one by one. Sometimes I exerted ferocious discipline to change only one thing and then go fly and see what happened. Nice excuse to escort the sunset. The airport critics developed a whole nother verse of how much work those gol derned Ezs take.

The operational expansion process has been fascinating to me, but tedious for those watching. When they come around, I sometimes mention that the airframe was not an issue, nor the CHTs, but only the oil cooling. And anyway the stories that they make up are better than my trying to explain what some particular little gizmo spoiler had done on the last flight.
The oil cooling elements have seen numerous iterations in an attempt to get cooling at full power, with only the minimum and optimum air introduced.

Yesterday it did it. It helps that the plane has flown six days in a row, three times. Did I say that right? Over 18 flights in the last 30 days and still counting. The tedium aside, I love it.
Yesterday I had finally remembered to attach some twine to the right canard tip so I could again enjoy the very tame canard tip vortex. Per the normal drill, I knew that I would have time to take off and get to 2500 feet over the airport and run for a few minutes before backing off for the oil temp. I was watching for traffic and enjoying the pristine twine vortex and noticed after a third scan pattern inside that the oil temp was stable at 210. Several images of retesting the gauge passed through my mind. It took three oil temp gauges from AC Spruce to get an accurate one. This one was right on. A good secondary indication was the oil pressure.
Wow. Suddenly the canard tip vortex was not nearly as alluring as the gauge needle. I hadn’t known that so much pleasure could be derived from watching a needle not move. I had made another iteration in the ducting the night before but with the hot day I didn’t expect any improvement. The thrill of the flight was to open her up a little more and with the added speed, watch the oil temp lower from 210 to 202. Miraculous. Even after landing and putting the plane away I don’t think my feet touched the ground but every third step.
Thursday. I sit here tonight again, radiating from the day’s runs. Two runs. The first was in the heat of the day to confirm yesterday’s numbers. The miracle held and it was a good run and after landing and refueling I started to taxi back to the hangar. But the sky was purpling up with the gold glow just getting going good, and it was cool, and it would serve a technical purpose to watch the temps on a takeoff when the engine was still hot. Any reason will work. The rose-hued takeoff was spectacular, with a couple of friendly comments from the taxiway gallery. Airborne again, I could heartily feel the difference of tons of jettisoned temperature distractions that had been bogging down the previous flights. For the whole 0.8 there was some kind of control problem, just couldn’t keep her straight and level. 205, another wingover. 202, another wingover. 195, another wingover. 190, another wingover.
Inbound at dusk the plane was zipping along as smooth and sweet as anytime I remember. I think it’s Hertzler’s prop. Anyway, I called entering for an overhead break. A taxiing KingAir announced they would be taking the runway, so I extended a little to let them get going. They stopped at the hold short line and a different deeper voice announced that the KingAir would be holding to watch the Eze land. Gave them a pretty good one.
DetailsMore to come, but basically there is now a little smile of an inlet in the lower cowl about 14 inches wide x ¾ inch where the mustang scoop would normally be. It puts air on the oil pan and creates a rearward flow along the inside of the lower cowl that also draws air through the oil cooler, which, after three other locations, is again mounted a couple of inches aft of the spar with a 1.5x5 inch male scoop under it. This scoop in the mustang location will be minimalized a couple of times before finalizing it and making it look socially acceptable, as well as the oil cooler scoop.
The difference now is that there is enough proper air draw for the air coming in the oil cooler to get out of the back of the cowl. Should have done that first!
Specifically, exit air ramps a la Cory Bird’s yellow plane are used on the lower cowl aft of the lower plenums. Picture in March 06 SPORT AVIATION in the cooling article. The excellent article also points out details on the NACA inlet.
A few days ago the test flight included a reworked outer lip on the right NACA inlet into the plenum. By improving the inside surface and thickening the lip more like described in the article, the two CHTs on that side lowered about 20 degrees. Details, details. Wish I was like you guys and got all this right the first time. There is still more to be tried from that article. I have read it about ten times and am still chewing. Looking backWhen Avery initially talked about sending some stories in, I declined, since I wasn’t flying at the time. A little later somehow he found out that I had flown the 0-290 and said it was time for me to start sending in notes. Since there were a couple of fairly unique 0-290 engine installation details to peruse, the development and test flights were very deliberate. Not being entirely confident of what I had wrought, I confirmed their operation while kinda reluctantly sending some of my favorite non-0290 notes to Avery and you guys. I feel better now. Today I am an expert on oil cooling, Tomorrow? Well, we’ll see.
Little by little, the elements were validated. One irresistible, distracting, counterproductive practice that I couldn’t get away from was with any glitch, to immediately suspect my new component as a culprit.
Early on, in fact, an erratic rough engine was caused by a leaking intake valve where the oil sucked in fouled the plugs. That intake valve problem was isolated with the help of our senior A&P and it was taken for repair. A month or so later, the engine was running erratic and rough again. After much head scratching and watching his mastery of troubleshooting, the same A&P helped determine that it looked like they fixed the wrong (exhaust) valve out of habit rather than the intake. I removed it and took it back and they disputed that they did the wrong valve, but graciously offered to do the intake for no charge.
Not long after, it was erratic again. After holding a gun to all of my components again, we confirmed it wasn’t oil fouled plugs, but isolated a cool cylinder and took the aircraft spark plug to the A&P and he tested it in his pressure contraption and reported was firing but had an orange spark instead of blue, which was defective. Less than 30 hours on it.
That sequence was fairly tedious, but interesting, and from my position looking back right now, very rewarding.

Many of the flights were perplexing. On a couple of nights I had the challenge of trying to go to sleep after observing airflows in oil in the cowl that were the opposite of what I had expected. I have mentioned in the past that I don’t think that the prop always pulls air out of the cowl… I hate when that happens. If you look at the March SPORT AVIATION article close enough, you will notice him say something similar, referring to an aft facing outlet I think.
The flush of today’s success has spurred several notes. Some on the technical details may be interesting. One set of gizmos that were very useful were four little spoilers that were made by cutting a 4 inch long, two-inch aluminum pipe lengthwise into four curved strips. They were temporarily riveted in a few places as spoilers and did in fact generate some additional exit airflow, which I observed as reduced temps on that side. Am working on some pictures.
Have a very good day y’allBill James, Fort Worth VariEze

Fun Flights

2005-02-28T11:00:00.000-08:00

VariEze N95BJ flew 1400 sm non-stop from Fort Worth Tx. to Reno, landing in Truckee, Ca. in just under 8 hours at 11.5K, 175 mph, on 31 gallons at 3.8 GPH. I hope to make the trek again soon with the 0-290.The normal drill when not grinding on the plane is to fly 15 to 20 sunsets a month, plus a few trips. At Oshkosh one year a man was asking about the plane’s speeds and ranges. I laid out my 5 foot wall map on the strake showing the tracks from Fort Worth to Reno, Atlanta in 4.5 hours, Denver in 4:02, Oshkosh nonstop in 5 hours, to San Antonio to see my folks in 1.5 hours instead of the six hour drive… Another man spoke up with an accent, asking “Who give you permission to fly all these places…?”

That Oshkosh memory renews appreciation for our country and spurs the recurring sunset emotion, “Burt, the Wright Brothers would have killed to be doing this.”

A fellow at a fly-in had been studying the airplane and taking notes for a good while and said, “So, your plane has side windows, wider hip and thigh room (condensed consoles), harmony in pitch and roll; the strakes are aerodynamic, structural, have elbow room in the front seat and baggage space in the rear, thirty-five gallon fuel capacity; the wings are level with no anhedral; there are access panels for the nose, canard, instrument cover, a belly hatch; and those and the wheel pants are held in place with rods—no screws; including the cowls that come on or off in a couple of minutes; cooling plenums, that weird prop…”So,” he says, “…of all the things on your airplane, what do you like best? The best thing to have on the plane? Bug guts.