Latest info on the crash

[LouP]

Well the facts are finally being told, that the guy is a hero. I have heard so much C^%& about how this happened because the pilot was old and should not have been flying, that it was just making me sick!


http://www.cnn.com/video/#/video/bestoftv/2011/09/20/ac-reno-brent-wilson.cnn?&hpt=hp_c2

LouP

 

[SPman]

He's not a hero - he's dead. It wouldn't have mattered what age he was, once the trim tab went, he was not in control, nor probably, even conscious.
It's just a tragic set of circumstances.

 

[Thoe6969]

I am also tired of hearing about his age also,which had nothing to do with it ,but also hearing that he was a hero,the experts say he was out like a light and was just along for the ride,which could be seen in close ups of the plane coming down .There was no head visable in the cockpit.

 

[JAllen]

No fireball on impact? Nothing ignited the remaining fuel? The impact dispersed the fuel so fast there wasn't enough of it to burn? G forces must have been huge as that plane rolled into a dive. The pilot couldn't have done much while being shoved into the floor so no wonder his unconscious head was not visable.

Jim

 

[Bomber_12th]

This has been circling around the racing/warbird community, which reportedly are numbers taken from the aircraft's telemetry system.

- Speed around the #8 pylon - 500mph at 102" Manifold Pressure
- When the trim tab let go, 22.6 G's were experienced
- Speed decayed to 375mph then accelerated again to 500+mph just before impact

At this time, this is still regarded as speculation and not yet verified by those in charge of the investigation, but if even close to the truth, that tells the real story.

In some photos that have emerged showing the aircraft after the pitch-up, it is also clearly evident that the fuselage, just behind the wing, was bent, as 'oil canning' can be seen in the fuselage skins - another result of the amount of force that was put on the aircraft and pilot.

One of the people who was in the audience that witnessed the event, who is a long-time Mustang owner and very experienced pilot himself, has stated that when he saw the pitch-up happen, he felt right there and then that the G's must have been 20+, just based on his own experience in both flying warbirds and aerobatic aircraft. Obviously anybody, of any age, is going to be highly affected by that kind of force. One aeronautical opinion is that due to the wings being shortened, they could have withstood a larger amount of positive G than the stock wing, without failing.

The fact that there was no fire/explosion upon impact, is what has also been talked about a lot. Some information about the aircraft may help to explain this -

- Aircraft participating in the races, are only fueled up with enough to get them through the race, and not much more, due to wanting to limit the weight as much as possible.
- Galloping Ghost had water onboard the aircraft, for the boil-off coolant system installed.
- Large chunks of blue foam-like material can be seen at the site of the impact. It is believed that it is of the material installed into the fuel tanks, to prevent an explosion/fire if a crash/forced landing were to occur.

 

[magoo]

That's unreal. A few degrees off, he could have impacted right in the middle of the spectator section.

I imagine these planes carry the lightest possible fuel load. That, and any fire supression technology built in to the racer certainly kept the cassualties down. Imagine a fireball at that proximity....

I think the distribution of the visual image via internet media is something new. There have been crashes before, but the type of coverage this one is recieving may dictate that governing interests may have to do something dramatic in order to satiate public expectation. It may be only so much as moving back the spectators. Perhaps the unlimited class may be dropped. I don't think there will be a complete cancelation of any further racing. But people talk. ( Here I am....)

One question about a P-51: Are the left and right elevators connected or can they move independantly? ( A benefit in regard to combat damage..?)

I'm wondering if one trim tab detatched, would it be enough to overwhelm control so abruptly?

(One could also appreciate that even if the pilot could manually control the event, he would have to be in a position to understand and react before blacking out due to G-force....)

EDIT: While I was typing, thanks for comfirming fuel details, John.

 

[Gibbage]

A few facts.

#1. The trim tab left the aircraft after it strayed from the race course and was already in a terminal position (Inverted less then 500ft up).

#2, The tail wheel is clearly down by then, but mains were not.

Something happened in the tail area. The pilot left the race course and that put him over the grand stands. Somehow he got inverted and pulled up. My guess is a control line snapped, taking the hydrolic line out with it. Once the line was snapped, it caused a flutter on the elevator that broke the trim tab off.

As for the lack of a fireball, its a race aircraft. They only carry enough gas to fly a few laps and land. He also carried as much water as he did gas for his cooling system. All these factors make it less likley that it would of created a fireball.

Here are two good photo's that show the situation. First, trim tab gone, but positive force on the elevator.

2nd, terminal dive, no elevator input, no pilot (possibly slumped down) and tail wheel down.

 

[oakfloor]

Yes. I heard it all, "He's too old", "Why are they racing?", "They should ban air racing" With so many experts around why dont they work for the NTSB? However this is why they discontinued the cleveland air races when a '51 crashed into a house, killing several people IIRC. The reno air races have been going on since 1964? and there have been up until now only 19 fatalites for the worlds fastest motor sport. Not bad compared to other motor sports.

 

[Bomber_12th]

Kevin, the trimtab appears to have departed, mostly, from the port-side elevator, which is agreed to have been at the point the pitch-up occurred, but remained attached until around the time the aircraft went inverted, at the top of the climb, at which point it completely detached from the aircraft. Contrary to early reports, according to all race participants, there was no mayday call, except for a 'red flag' call made immediately after the incident took place. In order to depart the race-course for any reason, a mayday call would have been made before ever initiating a pull-out of the course.

 

[Gibbage]

That, along with the photo's showing his head slumped down, leads me to think that he was passed out from start to finish. I just have a hard time understanding how the trim tab on an elevator could invert the aircraft. My guess, knowing the laminar wings tendency, is it snap stalled inverted after a VERY sharp pitch up. The pitch up could of been caused by the trim tab, but not the rolling. Its also possible that the pitch up put so much G's on the tail wheel that it broke the lock and lowered it. Its a very possible scenario.

 

[magoo]

I just have a hard time understanding how the trim tab on an elevator could invert the aircraft.

....Re: My wondering above if any know about P-51 elevator design, if they have the ability to move independantly under certain circumstance.

 

[Gibbage]

No. Trim tabs are mecanically linked to the single trim wheel in the cockpit. There is no way for the pilot to control just 1, and no need for it. 1 trim tab should NOT be able to flip an aircraft, since most light GA aircraft only have 1 trim tab on one side of the elevator.

 

[Willy]

Most GA aircraft aren't traveling 500mph either.

Let's not make this an "I know more than anyone else" contest or it'll be closed.

 

[Bomber_12th]

For anyone who is interested, here are some diagrams from my copy of the giant P-51D/K "E & M" manual.

Both elevators are connected to a centralized elevator horn assembly, so they are not independently controlled. I'm not saying it is related to the Galloping Ghost incident, as I have no theory or idea in my head in regards to the elevators being involved, but the only way in which one elevator would be un-controllable, would be if it were to detach from the center elevator horn assembly (whih would be really odd), where as the other elevator would remain controllable. If the control lines were to snap or become loosened (which I am also not saying happened), there wouldn't be any elevator control.

Both elevator trimtabs work together, through the elevator trim-wheel in the cockpit, in the stock-form, though there are other aircraft out there in which only one elevator trimtab is used to control trim via cockpit-control (though not on any Mustangs that I am aware of). Now, there is a report that in photos of Galloping Ghost, from earlier in the week, that only one elevator trimtab can be seen deflected - that being the port elevator tab - and that may very well have been what was incorporated into the modifications - all will come out soon enough.

In the case of the stock aileron trimtabs on the Mustang, only the port-side aileron trimtab is connected to the aileron trim wheel - the starboard aileron trimtab is only there for ground-adjustment.

 

[Lateral-G]

http://ignomini.com/reno.html

 

[oakfloor]

No. Trim tabs are mecanically linked to the single trim wheel in the cockpit. There is no way for the pilot to control just 1, and no need for it. 1 trim tab should NOT be able to flip an aircraft, since most light GA aircraft only have 1 trim tab on one side of the elevator.

Most GA aircraft dont go 500MPH and have 3000+HP pulling them along, A P-51 at that power setting will have some down elevator trim to keep at level flight, because that much power the aircraft will want to climb, thats why theres two on a 51' so when it departs you got little or no trim tabs acting on the elevator, sending it up very fast. I read somewhere they calculated 22 Gs of force on the airframe, no one could withstand that much G force. Which is why the tail gear may have broke loose from down latch locks, and the seat mounts collapsed, and the pilots head cannot be seen. So yes it seems that the trim tab failing was a factor. IMO

 

[Gibbage]

Trim tabs only help deflect the elevator. If there was sudden loss of the tab, the pilot would be able to feel it and correct quickly. Also, black-outs are not instant, no matter HOW many G's you pull. It takes a few secons for the blood to rush down, and a few more to starve the brain to blackout. Anyone can survive 22+ G's as long as its not SUSTAINED G's. Thats why I am sure that if the trim snapped, the pilot would of accounted for it quick enough before the G's took him out. Also, trim tabs cant apply more force on a control surface then the pilots. They only help with pilots fatique, not control the aircraft.

P.S. Mig-15 only has 1 trim tab on the elevator. It had a max speed of 668MPH. The Mig-17 was a much more improved Mig-15 to remove some of its high speed handling drawbacks, and it too had 1 trim tab on the elevator.

 

[Bomber_12th]

Kevin, the whole trimtab-departing scenario has happened before, and thankfully that time the pilot survived. Based on that experience, it is absolutely known what 'can' happen when a trimtab departs from a Mustang at race-speed: http://www.warbird.com/voodoo.html

To keep a Mustang in trim, at near 500 mph, meaning that the airplane won't want to climb with neutral stick control, a significant amount of down elevator is needed, as the airframe isn't meant to stay at those speeds in level flight - the VNE "never-exceed" airspeed in the stock P-51, is 505 mph, which could only be attained, in a stock P-51, by putting it into a dive. The most you could usually hope for, even at max power, in a stock Mustang, is around 380-400 mph at best, especially at low altitude. At 500 mph, I would imagine that the Mustang could very well want to climb at 5000 fpm or more, without any trim input - it can maintain an extended 2,000+ fpm climb on high cruise power alone, going 170-175 mph.

As I've mentioned before, although the stock P-51 had two elevator trimtabs that worked together at the same time, it seems that only the left elevator trimtab on Galloping Ghost was being worked through the elevator trim wheel inputs. This may be an issue that is near the center of the investigation. My personal questioning, is how much more effective would the elevator trim be, with two tabs working together (as a stock Mustang has), than just one (as Galloping Ghost may have had) - in other words, would more nose-down trim be needed with only one tab in use, compared with that of both tabs in use, to get the same result. If so, perhaps there was more elevator trimtab deflection, from that single tab, than there would be from both tabs working together, to get the desired affect in-flight. I also wonder about the possible asymmetrical effect, in the original stock configuration being changed.

 

[Barfly]

I received this email from a friend's dad, but have not verified it's origin. It raises some interesting points about modifications to aircraft:

"The pilot isn't visible because he's likely doubled over due to the incredible g-force involved. When Hannah came to in 97, his body was doubled over and stuck under the instrument panel. He had to unstick himself before he could regain control of the aircraft. Jimmy never woke up. In Bob Hannah's incident, the climb to 9000' reduced the airspeed and thereby the g-forces enough for him to wake up and regain control.

As to the trim tab causing the problems... Some of it is VERY scary from a safety standpoint. The right trim tab was bolted neutral to reduce drag. The left trim tab was changed from mechanical adjustment to electrical. This means the left trim tab was handling ALL of the pitch trim loads on the entire tail creating huge asymmetry in aerodynamic forces, which is likely why there were reports of people seeing the fuselage skin rippled when he was headed down the 'valley of speed' prior to pylon 7. Basically the fuselage was twisting.

Additionally, the removal of the belly scoop/radiator assembly to further reduce drag, also removed a nose down pitch moment on the airframe, meaning the elevator trim had MORE force to overcome compared to a stock P-51.
In the P-51D flight manual, there is a warning stating not to use more than 4 degrees of elevator trim at speeds over 400mph as they trim tab can suffer failure, and this is for a STOCK P-51 with both trim tabs operating.

During early qualifying, Jimmy had run the airplane around the pylons at a little over 70" of manifold pressure, with a speed of around 450mph. Basically the engine just wasn't working very hard (for a Reno Race prepped Merlin engine), but telemetry shows the engine running at 105" of manifold pressure at the time of the crash. Basically the airplane was flying faster than he'd ever flown it before. There are reports that people got him on a radar gun going through the valley of speed at 551 mph on the lap before the failure but that hasn't been confirmed.

As to the sequence of events, most people in the know now believe this is what happened.
1) Trim tab fails (not gone yet.. just mechanically has failed).
2) Elevator moves to full up as a result causing a nearly instant 12-14G
3) The failure of the trim tab also causes significant flutter in the tail. This intense vibration breaks the tailwheel uplocks allowing it to extend.
4) This puts Jimmy unconscious, slumping him forward onto the stick causing the roll to inverted
5) Now inverted, the failed trim tab and up elevator causes the aircraft to dive into the ground.
Some facts:
1) There was no mayday call. The NTSB has confirmed this.
2) The engine never changed power settings until the point of impact "
__________________

 

[oakfloor]

Barfly, and Bomber I think you guys have great info and well thougt out and informed posts. Finaly some straight facts. Thanks for the accurate info, Could you post a link to the telementry info?