Gary Palmer wrote:

Hi all,
        The discussion on RV-6 spin behaviour prompted me to pull out an old posting from a good friend with several hundred hours in an RV-6 who attempted some spin testing and managed to really scare himself.

        The RV-6 and RV-7 are very different from the RV-3/4/8 tandem aircraft in their behaviour. Wolfgang Weichert is the original poster and a very experienced pilot who is also an aerobatic instructor on gliders, so he knows what he is talking about. Wolfgang and I flew to Fulton NY a month ago to meet VAN, and Wolfgang raised the spin subject, and VAN confirmed that his observations were accurate, the RV-6 winds up exceptionally fast and takes 2 to 3 turns to recover from a developed spin. He also indicated in response to my query about the RV-7 larger tail surface area perhaps ameliorating the spin, that unfortunately the RV-7 spin characteriistics were essentially the same as the RV-6.

Original post follows:

        > I heard that Van's does not recommend spining their planes. Can anyone clarify > this? I had thought that it was the whole series, but maybe just the 6 > series? > What is the reason? Speed buildup or recovery? Have any of you spun one?

        > > rich Yes, I have spun the RV-6. Let me first give you the reason for doing so: In Canada, most homebuilts are restricted to NO AEROBATICS unless evaluated by a technical committee. 2 years ago this changed. The owner can evaluate the aircraft for the type of aerobatics he wants to perform, and sent a request and report to Transport Canada. The evaluation includes spins and recoveries. That was the reason for me to do spin evaluation.

        I have a couple thousand hours experience in gliders and tail draggers, I enjoy spinning gliders and Citabrias and other aircraft, and I have the training and experience for spin recovery. I flew the tests at 6'000' with parachute, half fuel and no luggage. The first entry was to the left, with recovery initiated after half a turn. Entry into the spin at idle power was snappy, with quick rate of rotation and pronounced nose down attitude. Recovery was normal. Second entry was the same but recovery initiated after 1 turn. Recovery was normal at first, but then the aircraft flicked to the right like a spin entry to the opposite. This was recovered from before it could develop. Next entry was as before but to the right, for a complete turn or slightly more. Normal recovery action failed to bring the aircraft out of the spin. Various recovery techniques were initated but failed. I finally let go of the controls and aircraft recovered by itself with nose down attitude. Du!

ring the last spin I had lost 2'500' altitude, was down to 3,500'. At that stage I disccontinued with that evaluation. wolfgang.weichert@nrc.ca

        I think this experience clearly highlights the potential risks we all take when test flying our homebuilts. When a designer says spins are not recommended, he probably has a good reason. And just because several of his designs have good spin recovery behaviour, doesn't guarantee all of them will. Test pilots certainly earn their keep IMHO.

        I lost a good friend when the Lancair 235 factory demo plane went in at Fond Du Lac a few years ago, and had noticed when flying with him, that he had a tendency to make a very tight turn to final; something you can get away with if you have lots of speed. The Lancair, like the RV has very benign stall characteristics, but even lighter pitch control forces so speed control on approach is very important. I agree with an earlier poster, that an AOA indicator coupled with an audible warning would be a great safety addition

Fly safely friends.......Gary

Gary Palmer
Lancair 235 C-GPLM
President EAA Chapter 245
http://eaa245.dhs.org/
gpalmer@NortelNetworks.com

 
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