Video here,
Counting on analysis from the Colonel:
https://nypost.com/2020/01/30/aerobatic ... -in-video/
Chambliss Team Crash
- Colonel
- Posts: 2546
- Joined: Wed Jan 15, 2020 10:02 pm
- Location: Over The Runway
From what I can see, he simply started the pull from the vertical downline at too low an altitude -
the radius of his pull was just too large, and he hit the surface/obstacles.
It looks like he had plenty of alpha on - doesn't look like a G-loc to me - so I don't see a technique
error in the pull, from the vertical downline to level. See, if you don't pull enough G, you give up
radius, and if you pull too much G, you stall and lose lift and radius increases. You actually want to
pull at Clmax - see my note on the physics of this - and hope that's within the ultimate structural limit
of the aircraft you are flying, at the speed you are flying. See the corners of the Vn diagram.
Pointed at the ground down low, sure, exceed the design structural limits, wrinkle the airplane, but
land very gently and immediately and live to fly another day, even if the aircraft is now junk.
Note if you exceed ultimate structural limits, you can expect the aircraft to fail in flight. If you
exceed design structural limits, you might lose some bits and pieces but the big parts might stay
on, even if they are permanently altered (see Young's modulus: stress vs strain and elastic vs plastic
deformation).
"Top Gate" comes to mind. What is the lowest altitude that you are comfortable, being in a vertical
downline? You must always have the height required for the radius of your aircraft Vs at that density
altitude. Without that, you crash. It's really very simple.
Like many other dead aerobatic pilots - like Jim LeRoy, Marcus Paine, etc - another 100 feet of altitude
would have probably done it.
On the subject of bending airplanes, anyone remember the 747 that went supersonic over the Pacific,
and permanently bent the wings? Boeing looked at it after it landed and said, "Fly it".
Fuck me. No thanks. When an airplane is wrinkled, melt the fucker down and make canoes, but I've
just been working in industry as an engineer for over a third of a century, so what would I know?
Ask Bob Sterling and his wife about this. More dead friends.
the radius of his pull was just too large, and he hit the surface/obstacles.
It looks like he had plenty of alpha on - doesn't look like a G-loc to me - so I don't see a technique
error in the pull, from the vertical downline to level. See, if you don't pull enough G, you give up
radius, and if you pull too much G, you stall and lose lift and radius increases. You actually want to
pull at Clmax - see my note on the physics of this - and hope that's within the ultimate structural limit
of the aircraft you are flying, at the speed you are flying. See the corners of the Vn diagram.
Pointed at the ground down low, sure, exceed the design structural limits, wrinkle the airplane, but
land very gently and immediately and live to fly another day, even if the aircraft is now junk.
Note if you exceed ultimate structural limits, you can expect the aircraft to fail in flight. If you
exceed design structural limits, you might lose some bits and pieces but the big parts might stay
on, even if they are permanently altered (see Young's modulus: stress vs strain and elastic vs plastic
deformation).
"Top Gate" comes to mind. What is the lowest altitude that you are comfortable, being in a vertical
downline? You must always have the height required for the radius of your aircraft Vs at that density
altitude. Without that, you crash. It's really very simple.
Like many other dead aerobatic pilots - like Jim LeRoy, Marcus Paine, etc - another 100 feet of altitude
would have probably done it.
On the subject of bending airplanes, anyone remember the 747 that went supersonic over the Pacific,
and permanently bent the wings? Boeing looked at it after it landed and said, "Fly it".
Fuck me. No thanks. When an airplane is wrinkled, melt the fucker down and make canoes, but I've
just been working in industry as an engineer for over a third of a century, so what would I know?
Ask Bob Sterling and his wife about this. More dead friends.
45 / 47
-
- Posts: 334
- Joined: Thu Jan 23, 2020 4:25 pm
One thing that made air displays safer for us in Europe was their strictly enforced rule that you could not go below two hundred feet above the surface during an display.
-
- Similar Topics
- Replies
- Views
- Last post
-
- 0 Replies
- 2914 Views
-
Last post by News
-
- 0 Replies
- 6773 Views
-
Last post by Scudrunner
-
- 18 Replies
- 13659 Views
-
Last post by Eric Janson