George,

Here is another video that some of the smart fellers out here think may demonstrate gyroscopic forces on the airplane.
The longer arm of the turbine propeller, acting as a gyro, is thought to cause an uncontrollable condition.  Similar geometry to a turbine LIV.
http://www.liveleak.com/view?i=bbe_1250712882

Bruce

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From: George Wehrung <gw5@me.com>
To: lml@lancaironline.net
Sent: Tuesday, January 8, 2013 1:10 PM
Subject: [LML] Re: Stalls & Spins

Skip,

Thank you for the video and explanation. I too was a Naval Aviation Safety Officer, T-34C flight instructor, functional check pilot, and taught the high and low out-of-control syllabi to new instructors.

So although, I am familiar with spins, progressive spins, spirals (had a few of those because of bad elevator/aileron rigging), high and low altitude departures I have no interest in spinning our Lancair.  I am interested in slow flighting and learning where and what the stall indications are for two purposes.  The first being to recognize the initial indications of stall onset and recovery for this airframe.  Secondly, is to calibrate the AOA system as we switched over from the separate AOA computer to the built in system within the Advanced Flight Deck 4000S.  I need to re-plumb the AOA tubing from the old computer to the advanced deck, then a calibration flight will be in order.  Once this is done and I have some data I will know the specific envelope to keep this plane happy.

In the mean time I am trying to learn as much as I can about this airframe from others who may have gone before me and to also have as accurate a POH as possible since I am gone and can't fly the plane till spring time.

Thanks again,

George

On Jan 8, 2013, at 8:29 PM, Skip Slater <skipslater@verizon.net> wrote:

George,

   Attached is the ES spin video Ron was talking about.  When I first saw it several years ago, I saved it. 

   The story behind the clip is that a builder hired an ex-Air Force fighter pilot to do his Phase 1 testing for him.  I swapped e-mails with the pilot after this came out and got the full story.  This guy took testing seriously, mapping out planned maneuvers for each flight, wearing a helmet and parachute and videotaping every flight.  One of the things he did was to perform a series of stall tests at progressively further aft CG's, I assume by adding ballast to the back of the plane, as he always flew alone..  Doing spins was not part of his test plan.  During the stall in the video, his CG was fairly well aft and as you can see, the plane unexpectedly and abruptly departed to the left.  He told me that when he applied recovery controls, the spin actually tightened at first but after nearly three turns and considerable loss of altitude, it did recover.  Had this happened at pattern altitude, recovery would have been impossible.  At that point he stopped doing any further stall testing and he told me that his recommendation was that spins be a prohibited maneuver in the ES.

   I got to do a lot of spins in prop and jet trainers in the Navy and would never even consider trying on in my ES.  I did approaches to stalls to calibrate my AOA (something I feel should be an essential part of any experimental's instrument panel), but have not done any since, as I can't even get close to stall speed now without the aural warning the AOA generates and would have to ignore it to do so.

   I'm with Jeff and LOBO on this subject - I don't recommend intentional stalls in Lancairs.  Because each is built a little differently, it's probable that each would handle a little differently at high AOA.  And as has been pointed out, the most likely place for a stall is in the traffic pattern and if you depart controlled flight there, all the training or practice in the world isn't going to help you.

   Skip Slater

   N540ES   

<ES spin.mpeg>--
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