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-   -   Big Crash at Reno (https://www.pprune.org/private-flying/463880-big-crash-reno.html)

172driver 25th Sep 2011 21:45

Video
 
It probably has no bearing on the accident, but what strikes me is that he lifts off A LOT further down the rwy than anyone else.

ULMFlyer 25th Sep 2011 22:12

172driver,

from the EAA article:

The ailerons are a little more than half the size of the originals, so the name of the game on final is speed. "Otherwise, everything gets mushy," he [Leeward] said. "I'm doing 190 mph on final, and touchdown [is] in the 150-160 mph area, which, by the way, Hoot Gibson told me are about the same numbers he uses in a Mig-21. It stalls at 130 mph (...)"

patowalker 26th Sep 2011 07:33


Quote:
the only other time i have heard of such an explosion-less crash was ken wallis' wellington during the war, and that was because it had been run completely dry.

You haven't heard much then.
Quote:

I readily admit that compared to the minds on here, ...
Nothing wrong with not knowing why the Ghost didn't explode, I don't know either, but to suggest that the last time there was an 'explosion-less crash' was 70 years ago is a bit OTT methinks. For recent examples search for "There was no fire" on the NTSB site. No use doing it on the AAIB site, because the search function is useless.

MichaelJP59 26th Sep 2011 10:58


Nothing wrong with not knowing why the Ghost didn't explode, I don't know either
Again, only speculation, but perhaps the very high speed near-vertical impact into the hard surface means that the structure of the aircraft and the uncontained fuel is dispersed too rapidly and widely for any flame front to keep up.

FoundationMetro 26th Sep 2011 13:13

"Again, only speculation, but perhaps the very high speed near-vertical impact into the hard surface means that the structure of the aircraft and the uncontained fuel is dispersed too rapidly and widely for any flame front to keep up."

Many years ago I read a story about the development of Napalm. They wanted to use an explosive to scatter it far from the impact site. But if they made the explosion too powerful, the speed at which it traveled simply exceeded the flame propagation rate and no fire occurred. I wonder if the crash conditions created conditions necessary to allow this type of to phenomena to occur?

CRayner 26th Sep 2011 13:34

Tailwheel down
 
Appears to be quite early on in the sequence. To my uneducated eye it looks as if it pops out well before maximum positive G. Perhaps some disintegration of mechanical structure in the tail section?

Lyman 26th Sep 2011 14:32

The tailwheel looked like a mechanical extension, not a broken mechanism, overcome by inertia. So is it possible that Leeward was configuring? His roll left at the beginning was controlled with right aileron, and the intitial climb seemed an input/climb. His later roll left (prior impact) mimicked a pylon hug, (there seemed to be some 'pull'); so had he started to regain consciousness?

Depending on the proximity of the high octane to the cooling Water/Methanol mix, the vaporisation rate may have blended the volatile fuel with water, creating a non explosive, non flammable (transient) mixture. High Octane Fuel burns more slowly than lower Octane, but I doubt that had too much to do with it. I guess about 40 gallons of fuel left, the size of an SUV fuel tank, so on its own, one would expect a fire, if only a brief (flash) one. Are we sure there was no 'brief' combustion?

Piper_Driver 26th Sep 2011 15:08


It probably has no bearing on the accident, but what strikes me is that he lifts off A LOT further down the rwy than anyone else.
Likely because of the shortened wingspan. Less wingspan = less lift = more airspeed required to take off = longer ground roll.

BackPacker 26th Sep 2011 15:21


I guess about 40 gallons of fuel left
Based on what?

I would assume that these guys run on the absolute minimum of fuel required for the race plus landing plus a very minimal reserve - perhaps just five minutes worth of fuel. Not the standard +10% +alternate +one hour reserve that is taught during PPL VFR training. In that respect, 40 gallons sounds like a lot to me. But I have to admit I don't know the typical fuel flow of such a racer, and I don't know how far into the race this accident happened.

mcgoo 26th Sep 2011 16:17

The Galloping Ghost specs quote 400 G.P.H at race power.

BackPacker 26th Sep 2011 16:23

In that case 40 USG on board at the time of the crash indeed doesn't sound all that extreme.

alexhara 26th Sep 2011 17:22

What had to have caused the Reno crash...
 
Very good article from a veteran aviator about what caused the Reno crash.

http://aerobaticteams.net/news/what-...aft-crash.html

Lyman 26th Sep 2011 19:01

I calculated seven gpm at full chat. Airborne for ten minutes, one third of which is "less than full go". Forty gallons at this stage of the heat is about right, perhaps generous.

He doesn't need more runway, necessarily, he has plenty gitemup to reach rotate v in a hurry. A measured acceleration, wild ass torque, etc. no 'hurry' to get in the air. With that wing loading, below 200 knots, I think caution is indicated. This is NOT an 'aerobatic aircraft'. It is built for velocity, stop.

Jim Howe's article is a good one, but a couple comments. First, the "g" was not horizontal, pushing pilot/seat back, it was vertical, pushing pilot/seat down. There was no wild g on the seat's rails, fore/aft, but on the rails and floor of the cockpit, down. This stopped as he reached the apex of the climb, and the a/c rolled gently, right. I too think he may have suffered a broken neck, but not from interference with the dorsal frame of the cockpit. Unless he had seriously tight straps, his chest went forward, and down, onto his lap. The rotation of the initial climb would force his head to roll forward, to subject it to the full force of the ascent.

The first problem with this flight was not the climb, as Jim has written. The a/c was rolled just right to the left (exiting the turn), when it started to continue to roll left, and the wings were vertical. Jimmy stopped this roll with aileron, and the a/c started to roll out to level as it exited the turn. This then was followed by a sharp rotation to begin the g event.

I was not present at this race, so my call on the gee is subject to inaccuracy. I didn't see 10-12 gee. I saw perhaps 6-7, but less than gloc value for a healthy fit pilot.

Google 'GeeBee'. It makes the Ghost look tame.

BoaterNotFlyer 26th Sep 2011 22:40

In post 111, we see a photo of the Ghost on her back. Looking closely at the photo, we see a bowling ball sized object much lighter in color towards the front of the cockpit. Almost at the junction between the canopy and skin.
Now take a look at the photo in post 157 where he is sitting in the cockpit. There is open space almost up to the junction between the skin and canopy. Right where this round object appears in the prior photo.

I'm thinking that in the first photo that the object in the first photo is the poor man's head and he is out cold. His head is buried in the dash. People familiar with the configuration and his helmet colors will have better input. But in the first photo his seat back by the top is still clearly visible.

keezy44 27th Sep 2011 00:35

We were directly below the galloping ghost when it rolled inverted coming down at us. He had to be unconscious from the beginning. Nobody of any age can stay conscious with a 10G+ pull up. Voodoo had it happen a while back and the same thing happened with that trim tab failing.

treadigraph 27th Sep 2011 07:07

A suggestion on the WIX site is that the aircraft may have encountered wake turbulence from the preceding aircraft, hence the initial increase in left bank to what appears to be 90 degrees or more.

Also from WIX, 9g would have been sufficient to bring the tailwheel out - did that happen when Voodoo's trim tab went?

B2N2 27th Sep 2011 20:44


Very good article from a veteran aviator about what caused the Reno crash.

I have to call BS on that broken seat article. The pictures in post #157 clearly show no room or open area behind the seat.
Besides that is where the custom designed cooling system was installed according to the EAA article.
For now I'll go with the black-out after pitch up presumeably because of a malfunction of the elevator trim. Something that has happenend twice before with similar aircraft during the same type of race.

Deeday 27th Sep 2011 22:08


I have to call BS on that broken seat article.
Agreed. The author seems to imply that the violent pitch-up caused a massive g-force directed backward along the fuselage, which is clearly nonsense.
In such manoeuvre the g-force would be directed mostly downward, towards the floor of the aircraft, i.e. no sliding back. Instead, head slumping forward, especially if the seat belts were not fully taut.

Zulu Alpha 27th Sep 2011 22:22

This photo has been posted elsewhere. It seems to show buckling of the fuselage.

http://www.aafo.com/hangartalk/attac...8&d=1316247134

keezy44 28th Sep 2011 00:01

I think when he did the 10+G pull up when he passed out who knows what his arm and body did to the stick. We saw the whole thing overhead and it appeared no throttle or control movements were made, it just was a projectile not controlled by anybody. Even though it looked like it would hit our seats for a couple of seconds I think time slowed down in our brains and it was less than a second after reviewing the videos.


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