Warbird Information Exchange

It's not that clear from the video, but it certainly appears that the jet is in/above the clouds at the top of the loop, and that it's in some rolling motion when the camera picks it up again.

Could just be the camera and the digitization, though, for both.

I have no idea of the performance envelope of the L-39, but it seemed like he entered that second loop awfully slow. It also looks like he was certainly being cautious, no overly dramatic manouvers or close passes.

That's an awfully rough thing to have to see at a show. God be with him.

Lynn

Here is a more clear video:

http://www.visualdissonance.com/ticoair ... V01702.MPG

Godspeed

It's always way too easy to Monday-morning quaterback such accidents, but, at the same time, some debate/discussion can be worthwhile. Here's what I see.

I believe the L-39 min loop entry speed is 320 kts - and if you plan on doing something on the vertical down line, you'll need more. Difficult if not impossible to judge his speed from the video, but it does look a bit on the slow side.

When he pulls into the loop, looks like he has the stick back to the left a bit, which is easy to subconciously do if the crowd/reference line is to the left, and you look at the wing too soon. The net result is that when he comes over the top, he is slightly banked left (from inverted). His routine looks like a roll to the right, so he has to correct back. As he does this the plane is continuing to arc over, which puts his angle at the start of the roll steeper than planned, I suspect. Also, punching through that cloud may have caused him to pull a little harder (subcounciously) and flatten the top, giving up some altitude and energy.

When he rolls on the down line, it looks like he is pulling too, which is a no-no in my book in a L-39 or any plane that can quickly get into an accelerated stall in such a position. Generally you would set a down line, roll, stop at a set bank angle, and then pull. The plane looks like it snaps a little in the roll/goes off the roll axis, so he may have in fact stalled it or hit buffeting, which could cause a momentary loss of control, with associated loss of altitude.

A bad, sickening deal all around. I understand it was also the guy's first airshow(?) year. If that was the case, he would have had a "hard deck" at 700 if not 1200 ft, so he missed by quite a bit. I'm kinda surprised he got the waiver, given what I see.

The announcer even says he is going to do a 1 and 1/2 roll on the downside which should have had him coming out the opposite way.

I agree that the airplane is rolling off axis so he may very well have stalled or he saw the developing problem and continued the loop into the trees. Bad day for everyone.

I talked to a very high time L-39 driver yesterday. He told us that the initial stall comes on and if you don't immediately unload that the secondary stall is wicked and the L-39 will immediately snap.

That really sucks. I feel even worse as it was his first air show in it.

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Chris Henry
EAA Aviation Museum Manager

Very sad to hear,
Shannon and I met Elion in Palm Beach during our Vacation. I walked over to say hello after I saw him in his flight suit and figured he was the driver of the only warbird on the ramp at the La Bella Machina, a Ferrari/Boys and Girls Club event at PBI back in January. I introduced myself and we started talking about the L-39 drivers from up in our neck of the woods. He mentioned he was just flying with Danny McCue a few days before. I got his business card and figured we would run into him at some show down the road.

Our Condolences, Godspeed.

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"Hindsight is usually 20% off!"