Letter of the Day: Wooden Pusher aircraft

Builders:

The letter below comes from Art Blake.  It is referencing a comment that I made in the story: Steel tube fuselages, “Safe” planes and 250mph accidents. Art has obviously extensively studied the Corvair option, and after his letter, I will clarify my point on Wooden pusher aircraft. I print the letter here because Art sent it in as a public comment, and I think his enthusiasm for building comes right through. Words many of us can relate to.

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“Dear Mr. Wynne,
I am totally psyched. I have not been this excited since my youngest son was born.
The kids are settling into happy lives and are contributing to the Common Good. My wife is comfortably situated, and last fall I made up my mind- it is time for me to break these surly bonds, build an actual aircraft, and FLY !!
I have the requisite experience: tree houses, go kart, R/C planes, and I even set the timing on my old Chevy Vega, using a light !
After much agonizing and searching and consideration, I decided on my plane, and I decided to power it with a rebuild Corvair engine. Last week for my birthday, I got my Corvair motor and my plans are on the way. I’m 1/2 way through ‘Stick and Rudder, joined EAA, and have studied lots of the building techniques tapes. The plans for my Pride and Joy are on their way! I can’t wait to get started……

And now, now, I read that you would not fly in a wood frame aircraft with a pusher engine.

I’m flummoxed, astounded, flabbergasted, crushed.
I’m speechless, horrified, bothered and bewildered.

The craft I chose, and am so psyched to build and fly, is a Volmer V-J 22, “Sportsman” – yes, A WOOD FRAME AIRCRAFT WITH A PUSHER ENGINE !.
From your blogs, I have learned that you are not someone to give a gratuitous ‘pat on the head’ to someone who is about to so something you can not condone, but, can you throw me a bone, man?
Will I be building a deathtrap? Do I have to decide between (1) building The Flaming Comet as planned, or (2) riveting together a Belite, strapping on a 1/2 VW, and flying whining circles around the airstrip, like some angry hornet, until either the motor falls off, or I fly it into the trees, just to break the monotony?
I suspect you do not say things lightly, and I need to know – is this list of ‘safety preferences’ based on actual statistics, or is it a private opinion, a Gestalt, or the result of some bad experience(s) for you?
Help me out, I dyin’ here.
-Art Blake”

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Art,

I thought your letter was very funny, you are a good writer. When I wrote the comment about wooden pushers, I was specifically thinking of a Rutan Vari-Viggen, (which incidentally, actually flew with a Corvair for one builder in the 1980s) I admire Rutan, but not for that design.  You are quite correct that some opinions are formed from negative experience rather than pure statistics. At the very bottom is an excerpt of something I wrote about a disturbing day.

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Although the stall speed of a Vari-Viggen is listed as 48 mph, compare all the specifications on it’s Wikipedia page to those of a Van’s RV-4, another O-320 powered two seat plane. Although not perfect, the RV-4 probably has a much better statistical record than the 20 vari-viggens that flew. I have experienced friends who have built and flown Rutan designs (Arnold Holmes) and friends who chose not to (Dan Weseman).  I consider both of them very good at risk management, but they use their planes differently also.

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My comments don’t directly apply to the VJ-22, and I will tell you that I have many times considered building one. The low landing speed mitigates a lot of the wooden construction issues, but I would still put a plastic tank in it or a fuel cell, and I would carefully consider what type of terrain I overflew at low altitude. I do this with all aircraft, but my factors would be adjusted with a VJ-22.  Of course, it would be a very low risk in an engine out if you were over water. As the story stated, it is all about making your own decisions.

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The Corvair/VJ-22 combination has been done before. Below is a picture from our website of a plane built by Claude Delebruere, of Newport, Vermont. He flew it about 100 hours on a Corvair, and later went to a bigger engine. The link below the plane leads to other photos and a description. You can find obscure stuff like this on our main website by using the search box at the bottom of the main page:

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http://www.flycorvair.com/delabruere.html.

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Below, an excerpt from our risk management story: Risk Management, Wrong airframe, Wrong experience level. I am writing about a Sunday morning at an SAA fly-in in Champaign-Urbana Ill. The pilot who wisely stopped anyone from calling the man’s wife was our friend Doc Mosher. I was going to ask him how, in the chaos of the moment, he kept a clear line of thought like that, but later reflected that after 20,000 hours and five decades of flying, this was not the first accident Doc had seen.

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“If anyone wants to write me debating that pusher aircraft with composite or wood fuselages are not good test planes, please read the Vari-Viggen/O-320 accident report below first. I was on hand for the crash 10 years ago. I had spent the previous day admiring the man’s craftsmanship and personal style. He was a stand out in a group of 1,000 people at Frasca. The soy bean field he had a forced landing in was big and flat enough that I am pretty sure I could have landed at DC-3 in it. His fuselage did not protect him. It had poured rain the day before and it was later thought he had water in the fuel. With many planes this would have been an non-accident, but the man’s airframe choice did not work for him on that day. His wife had driven there and previously left for a 6 hour trip home. Some one was going to call her, but a pilot with 50+ years of experience stopped them so the woman could get all the way home and back to family before finding out she was a widow.”

http://www.ntsb.gov/aviationquery/brief2.aspx?ev_id=20020617X00903&ntsbno=CHI02LA166&akey=1

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About William Wynne
I have been continuously building, testing and flying Corvair engines since 1989. Information, parts and components that we developed and tested are now flying on several hundred Corvair powered aircraft. I earned a Bachelor of Science in Professional Aeronautics and an A&P license from Embry-Riddle Aeronautical University, and have a proven 20 year track record of effectively teaching homebuilders how to create and fly their own Corvair powered planes. Much of this is chronicled at www.FlyCorvair.com and in more than 50 magazine articles.

2 Responses to Letter of the Day: Wooden Pusher aircraft

  1. Martie Williams says:

    William, After reading the the NTSB report, (“The witness reported the airplane started a slow, nose high turn to the right, and gained about 200 – 250 feet of altitude in the crosswind turn. She reported the airplane looked like it was in “slow motion” and that the “delta wing just kind of hung there.” Approximately 7 – 8 seconds after initiating the turn, the airplane appeared to roll and the nose dropped to the right and impacted the terrain nose first.”) I’m not sure what construction material or type or what engine or engine location of the accident aircraft would have changed the outcome. Aborting the takeoff or landing straight ahead when he realized the extent of the problem seems like the only thing that might have really altered the outcome.

    • Martie,
      I see your point, but we were always taught in accident investigation that the least reliable piece of data available is often the eyewitness observer. I know 5 or 6 people who saw this first hand and their description would probably be different. I think the writer put the comments in quotes for a reason, to set them aside from purely physical evidence. Note that the observer claimed the plane stalled and spun, but this is something the Vari-Viggen is specifically designed to not be capable of doing.

      We could debate this particular accident, you from reading a 12 year old report, me from having been there, for another 12 years and come to not conclusion about this specific accident. My point in the story is to make people understand that there is zero rational argument that wooden pushers have less crash survivability than steel tube tractors. For a personal choice, you can elect to fly what ever you like, and the goal is to get each person to think about that for themselves. -ww.

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