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It looks like a trim tab fell off the elevator (tail) of the Reno crash plane..

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Fumesucker Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 12:07 PM
Original message
It looks like a trim tab fell off the elevator (tail) of the Reno crash plane..
http://www.kolotv.com/home/headlines/A_Pictures_Says_a_Thousand_Words_130007898.html

My understanding is that this would have caused the nose of the plane to pitch up hard at the high speeds they are flying..

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Dennis Donovan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 12:10 PM
Response to Original message
1. Buckminster Fuller - "Call me Trim tab"
http://en.wikipedia.org/wiki/Trim_tab#Trim_tab_as_a_metaphor

The engineer Buckminster Fuller is often cited for his use of trim tabs as a metaphor for leadership and personal empowerment. In the February 1972 issue of Playboy, Fuller said:

Something hit me very hard once, thinking about what one little man could do. Think of the Queen Mary—the whole ship goes by and then comes the rudder. And there's a tiny thing at the edge of the rudder called a trim tab.
It's a miniature rudder. Just moving the little trim tab builds a low pressure that pulls the rudder around. Takes almost no effort at all. So I said that the little individual can be a trim tab. Society thinks it's going right by you, that it's left you altogether. But if you're doing dynamic things mentally, the fact is that you can just put your foot out like that and the whole big ship of state is going to go. So I said, call me Trim Tab.

—Buckminster Fuller
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Duer 157099 Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 03:05 PM
Response to Reply #1
9. A metaphor we can really use right now
We all need to adopt the role of the trim tab these days.
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Dennis Donovan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 05:57 PM
Response to Reply #9
17. Sadly, no one thinks of themselves as a trim tab...
The key is to believe and act as you are, and the rest of the rudder will follow.
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cwydro Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:07 PM
Response to Reply #17
19. You got that right.
Keep that trim tab working and steer a steady path with the rudder. (more sailing than flying, but you get my drift)

Looks like the guy saved some lives as he went down.
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nadinbrzezinski Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 12:15 PM
Response to Original message
2. That photo pretty nails down the mechannical
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whatwasthequestion Donating Member (41 posts) Send PM | Profile | Ignore Sat Sep-17-11 12:16 PM
Response to Original message
3. Agree
It will be a while before they piece it all back together and draw a conclusion, but the way it came out of the pattern and dove into the ground, it seems liely that the trim tab broke off.
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MineralMan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 12:23 PM
Response to Original message
4. There may have been other mechanical failures as well.
In any case, I never attend air shows or flying competitions. I consider them to be too hazardous to bystanders in general.
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Fumesucker Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 12:29 PM
Response to Reply #4
5. I didn't mean to imply that there were not other mechanical failures..
A trim tab has come off at Reno before with slightly less disastrous results.

Fourth paragraph down..

http://www.warbirdaeropress.com/articles/voodoo99.htm
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MineralMan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 01:58 PM
Response to Reply #5
6. I'm not arguing with you. Truly. nt
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malaise Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 02:28 PM
Response to Original message
7. Looks like it was literally coming off in that photo
Press conference coming up on CNN in a few minutes
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 03:02 PM
Response to Reply #7
8. What I want to know is: why is the cockpit empty in this shot just before the plane hit the ground?
Edited on Sat Sep-17-11 03:28 PM by leveymg
Taken as the plane was about to crash:
But, here's how it appeared in flight last year (pilot's head clearly visible):

Finally, it's a rear-hinged canopy, as you can see in the last few seconds of the video, above - one doubts the pilot bailed out, unless the canopy re-closed afterwards (not likely).
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Boxerfan Donating Member (710 posts) Send PM | Profile | Ignore Sat Sep-17-11 03:06 PM
Response to Reply #8
10. Perspective from the side view & G-forces...
Just a guess...


Or he's unconcious @ or before the incident...

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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 03:14 PM
Response to Reply #10
11. Here's another side view: head clearly visible in the illust & video. No place for the head to go
Edited on Sat Sep-17-11 03:20 PM by leveymg
Even if the pilot was unconscious, and under high lateral Gs, he was presumably strapped in. You would still clearly see the helmet in profile.


http://www.youtube.com/watch?v=WLk3wwVrvwc&NR=1

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malaise Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:10 PM
Response to Reply #8
20. If that aircraft was going at 500mph
he couldn't handle the force with the problem. Hopefully he already had already passed out and didn't know what was coming.
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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 03:29 PM
Response to Original message
12. I don't believe a missing Trim Tab...
...would have catastrophic consequences,
or make an aircraft completely uncontrollable.

Many P-51s suffered worse battle damage during WW2, and made it home.

Admittedly, this was a highly modified unlimited racing plane flying at a very high airspeed (+400MPH?),
so I am speculating. I guess it is possible that a missing trim tab caused the crash.
It just seems unlikely to me.
My best guess is that the trim tab departing (falling off) is an indicator of deeper structural failure.

I do have a Commercial License (not current), time in High Performance Aerobatic Singles,
and am a life long sport aviation enthusiast. I even have an hour in the jump seat of a modified P-51.

Just my 2 cents.

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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 03:56 PM
Response to Reply #12
13. The info I saw was that he had just taken off - explains why the tail wheel was still extended
Edited on Sat Sep-17-11 04:03 PM by leveymg
So he would not have been up to full speed when the trim tab departed. I also have my doubts a trim tab failure on takeoff would necessarily cause the sort of loss of control by an experienced pilot. It is possible, of course.

I still want to know why the pilot's head does not appear in that last photo taken as the plane was nose down, perhaps 100 feet from the ground. The head should be far forward - but assuming he was still strapped in, you would clearly see it in the profile photo. Any ideas? Also, I thought maybe the pilot had bailed out - but, there's no report of that and that plane has a custom, rear-hinged cutdown canopy - could it possibly re-close if he bailed-out?





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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 05:34 PM
Response to Reply #13
15. The tailwheel should have retracted with the main gear.
That could be another piece of the puzzle.
That section of the rear fuselage can be crowded, especially with a retractable tail wheel & gear doors.
Possible mechanical conflict between the tail wheel retraction mechanisms and the tail surface control cables?
The cable that controls the elevator trim tab would also be routed through that area.

As for the pilot not appearing in the last photo,
there are only three possible explanations:

Case 1) He was transported to another dimension at the last second before the crash
like in the novel 1983 novel Millennium, by John Varley.

"Millennium features a civilization that has dubbed itself "The Last Age". Due to millennia of warfare of every type (nineteen nuclear wars alone), the Earth has been heavily polluted and humanity's gene pool irreparably damaged. They have thus embarked on a desperate plan; time travel into the past, collect healthy humans, and send them to an uncontaminated planet to rebuild civilization.

The time travelers can only take people that will have no further effect on the timeline: those who have vanished without a trace, or died without being observed; otherwise they would be changing the past, which risks a temporal paradox and perhaps even a catastrophic breakdown of the fabric of time. Though they collect everyone they can, they exert a great deal of effort on those destined to die in various disasters such as sinking ships and crashing airplanes (and once a century of Roman soldiers lost and dying in the North African desert). As such incidents leave no survivors to report interference and change the timeline, they can freely remove the living but soon-to-die victims, and replace them with convincing corpses they have manufactured in the future."

http://en.wikipedia.org/wiki/Millennium_%28novel%29



Case 2) Some techie or Photo Enhancer Computer Program
accidentally erased the pilot.

Case 3) Some weird combination of lighting, camera optics, glare, or canopy reflection produced the illusion of an empty cockpit.

Even if the pilot was unconscious, he would have been held upright and visible in the canopy at that angle
by his 6 (or 8) point harness.

My best guess would be case 2,
and let me EMPHASIZE the word "GUESS" in everything I have posted about this incident,

but the Tail Wheel STILL being fully down while the Main Gear is fully retracted in these photos
is MORE than unusual.... To me it seems very WRONG.
(Good catch, BTW.)

I grieve for the loss of this pilot, and this increasingly rare and beautiful aircraft.

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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 05:51 PM
Response to Reply #15
16. I can't think of a Case 4) Every other possibility is even less plausible, and less attractive
Edited on Sat Sep-17-11 05:53 PM by leveymg
This is weird.

The only sensible alternative I found scouting around was that the seat broke, and the pilot somehow dropped below the edge of the cockpit bulkhead. I looked at cockpit details for the P-51 and the standard seat is on a frame suspended from a cross-member and has a height adjuster, while some custom installations are bolted directly to the floor of the aircraft. Most of the racers have done away with the cross-member, as it originally had a heavy armor plating backing, and bolt the seat to cross-members under the alumunium/wood floor. It seems that if one of the custom seat mounting points broke, the pilot wouldn't move in any direction much, as the harness attachment points are to structural members, not the seat, itself.

I'll say it again. There does not appear to be anyone in the cockpit of that aircraft.
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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 10:50 AM
Response to Reply #16
39. Case #4)
The publishers purposely edited the pilot out of that photo
out of respect and consideration for the pilot's family and friends.

There is a high probability that this is the answer to your question.


I enlarged the photo on my editing program,
and it does appear that the pilot was airbrushed out.


I believe this to be the most logical explanation,
especially if this photo was released by an organization that had anything to do with the Reno Air Races.

Some publications will do this out of general Rules of Decorum.


The tail wheel still being in the fully down position while the Main Gear is fully retracted still bothers me.
I even spent some time yesterday unsuccessfully looking for a video that shows the gear retraction sequence on a P-51.
Of course, in all probability, that equipment on Full Race P-51 has been replaced with
light weight racing alternatives.








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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 11:29 AM
Response to Reply #39
41. Look at the other still photos in that sequence - still no helmeted pilot to be seen.
Then look at seconds 14-17 on the YouTube video that shows the aircraft approach from approx. the same angle - you can see the head in front of the rear bulkhead.

I don't see evidence of Photoshopping in the detail you post above. Point at what you mean - shadows, reflections, the shade of grey. Looks consistent with an empty transparent cockpit to me.
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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 01:15 PM
Response to Reply #41
48. I'm looking at the streak of uniform gray...
...that runs through the cockpit.
It is slightly darker and much more uniform than the background.
It looks to me like a blurred brush stroke.
It even brushes over (what must be) the closing lip of the canopy, and toward the bottom, this canopy separation is gone altogether.

This is easy and quick,
even with modest image processing programs.

This took all of 2 minutes, quick & dirty, and was much more difficult due to the angle, background, and color.
Black & white, low resolution would be much easier.


We KNOW the pilot didn't just disappear,
and the odds of a seat failure that allowed him slip below the level of the canopy are ZERO (in my opinion).
What remains must be the truth.
The pilot was either accidentally or deliberately edited out of the photo.

This morning, I believe it was intentional, out of respect for the family and friends,
especially if he had his arms up either in terror, or an attempt to get out.
This would be a thoroughly natural human reaction.

I haven't watched the Video, but will give it a look.
Editing video is as easy as editing photos.



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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 01:39 PM
Response to Reply #48
50. Sorry. I don't think the photos were altered to cut the pilot's head out.
Given that this has been a subject of controversy brought up at just about every news site I've looked at, I think that would have been acknowledged by now. I didn't say it was impossible to alter the photos, just that there's no evidence for that explanation.
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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 03:29 PM
Response to Reply #50
55. Never-the-Less, the rules of Physics still apply.
"When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth." ----Sherlock Holmes

1) The pilot WAS still in the cockpit.

2) It is not possible for him to have slumped down or fallen backwards below the canopy level
so as to not be visible.
There IS no place to fall backwards or slump down or seat collapse into.
During WW2, there were many reports of dead pilots slumped over the controls but still visible inside the canopies in these aircraft.

3)The only real world conclusion is that he IS still in the cockpit,
but is not visible in the photographs.
This can only be due to an accident of Optics, Camera Limitations,
or he was intentionally removed during the processing of the images.

Take your pick.
My choice is that his image was intentionally removed.
I really don't care what is being said on other sites.
Some of those people believe in Alien Abductions.
I don't,
at least not in this case.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 03:46 PM
Response to Reply #55
57. I agree. Either there's no pilot or the images were photoshopped.
Edited on Sun Sep-18-11 04:20 PM by leveymg
Both are highly implausible, and neither can be ruled out.

I can see, maybe (conceivably, but not convinced), photoshopping the clearest profile shot, but why also the other more distant approach shots that are clearly not fake? There is no pilot's head to be seen in those, either. You can see that if you enlarge the images.

No, the photoshopping explanation makes no sense for all the shots.

Did this guy bail-out down range? That was my first question. But, wouldn't someone notice?

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Dennis Donovan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:02 PM
Response to Reply #15
18. He was jammed back in his seat with the stick pulled to his chest...
...and the canopy of this P-51 was modified so that he couldn't be seen from a 90 degree angle.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 07:24 AM
Response to Reply #18
31. In a vertical dive, G-forces would force his head forward. Besides, his head would be visible
Edited on Sun Sep-18-11 07:40 AM by leveymg
in any position. That seat and the restraints do not allow much movement fore and aft or side to side, and none up and down. Even if he tried to stretch back, his head could be seen from the side. You have to take a look at other photos to appreciate that. Like this one where you can see the top of the seat back (red just behind and below the helmet) and how little room there is behind the seat to the back of the cockpit:



YouTube : look at seconds 14-17. http://www.youtube.com/watch?v=WLk3wwVrvwc&NR=1

Now compare with the final photos - There does not appear to be anyone in that cockpit in the final photos:
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Dennis Donovan Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 08:58 AM
Response to Reply #31
35. I never mentioned G-forces...
He could've been jammed back into his seat by standing on the rudder pedals (in a vertical dive, the pedals would be below him) and pulling the stick... more like HUGGING the stick... all the way to his chest/abdomen in a frantic effort to pull the plane to the north of the crowds (and missing them).

I'm a licensed pilot with a modicum of aerobatic training. To me, I cannot imagine what his last act would be OTHER than that.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 11:23 AM
Response to Reply #35
40. Look at the photos of the cockpit I've posted from every angle. No place to lean back
so far that his head would not be visible. In particular, the large top-side view where you can see the relationship between the pilot's helmeted head, the top of the seat back and the rear bulkhead. There simply is no room to lay back that far in that cockpit.

The only conceivable direction the pilot could go to disappear below the cowling line of the final photos would be down. We'd have to believe the floor and lateral support members had given way and the seat dropped. I don't think that's plausible, as the wing root crossmembers and landing gear would be down there. But, will look further for photos and diagrams of the area below the cockpit floor.
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awoke_in_2003 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 11:48 AM
Response to Reply #40
43. ok, you're onto it...
it was a plot involving a remote controlled airplane- Obama LIHOP.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 12:32 PM
Response to Reply #43
45. That's not my operating theory of choice.
You can feel free to take credit for authorship of that notion, of course.
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awoke_in_2003 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 01:31 PM
Response to Reply #45
49. well, you are not buying...
any of the plausible reasons ie. lighting conditions.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 01:42 PM
Response to Reply #49
51. I don't think that lighting conditions are a plausible explanation, either.
All I'm saying is that the pilot's head should be visible, but isn't in any of the photos that have been released. That is very strange, and hasn't been satisfactorily explained.

All I want is a rational answer, and frankly there isn't one that satisfies me.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 03:41 PM
Response to Reply #40
56. Here's a clearer picture of the cockpit - head could not move back or forward
Edited on Sun Sep-18-11 03:43 PM by leveymg
enough, or up or down, to disappear from profile shots. If the pilot's head is missing, it's either not there or the image has been photo-shopped out of the crash photos.

From Leeward's website:



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BobbyBoring Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 02:03 PM
Response to Reply #13
52. One possibility
He may have been bent over kissing his ass good bye.

You lose a 51 at that alt. and you're gone.
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Major Nikon Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 03:59 PM
Response to Reply #12
14. I agree
It just doesn't seem like that in an of itself would cause such immediate and catastrophic consequences. I've saw an aileron fall off an airshow plane doing aerobatics and it landed just fine.
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jberryhill Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 09:37 PM
Response to Reply #12
25. Not a lot of altitude to play with

One video made it look as if he tried to go flat, went into a climb, and was looping out of it.

But the diameter of the loop was greater than his altitude.

It could just be perspective, though.
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jmowreader Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:14 PM
Response to Original message
21. My guess: loss of control due to seat support failure
If the seat support breaks in an airplane, the pilot goes backwards--pulling the control device back all the way in the process. This causes the plane to pitch upward, stall and crash. This is one of the more popular ways to die in a Cessna, as the following exhibits:

http://www.check-six.com/Crash_Sites/N95KW-Cessna-Seat-Rails-1989.htm

This would ALSO explain why you don't see the pilot's head.

I"m not buying the trim tab explanation--this is a combat aircraft, designed so you can get it home with various parts shot off.
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Dennis Donovan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:16 PM
Response to Reply #21
22. Yeah... to hell with the pics showing the trim tab disintegrating...
:shrug:

The seat rails in a Cessna vs a North American P-51D Mustang? That dog CAN'T hunt...
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jmowreader Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:38 PM
Response to Reply #22
23. The picture I see shows the trim tab going straight back...
I don't think the trim tab alone would have done it. As I said, this was a fighter; they're made to sustain worse damage than that.

I used the Cessna example because it demonstrates what happens when the pilot's seat falls out of an airplane. Remember, this is a World War II airplane that had the armor plate behind the seat removed. If the seat support failed--even just the support for the seat back--the plane would have gone into an unrecoverable stall.
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Dennis Donovan Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 06:54 PM
Response to Reply #23
24. I'm sorry, but you're speculating that the seat failed because that's what happened in a Cessna?
I'm not trying to give you a hard time. When it comes to aviation accidents, I'm sensitive to speculation vs facts before investigations are completed. To me (I'm a licensed commercial pilot), the pic of the trim tab disintegrating indicates the beginning of a catastrophic event with the horizontal stabilizer/control surfaces. At speads above 150 kts, that's enough to cause this horrific accident.
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crazyjoe Donating Member (921 posts) Send PM | Profile | Ignore Sun Sep-18-11 07:43 AM
Response to Reply #24
32. well, I'm a anonymous poster spending too much time on the internet,
and I say a bolt came loose, the seat support failed, which caused the pilot to suddenly jerk back on the stick, and the result was an empty looking plane crashing into the ground.
mystery solved :-)
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The Velveteen Ocelot Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 09:57 PM
Response to Reply #23
28. The failure of the trim tab certainly could have caused this accident.
The P-51 was not designed for the high speeds of the air race, and even though it had been modified, it had to sustain enormous air loads. The faster an airplane goes the less deflection of any control surface is required to change the airplane's attitude or direction. If a trim tab fails the airplane can pitch up very suddenly, which could then place sudden and extreme loads on both the plane and the pilot, sufficient to cause an unrecoverable loss of control.
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Fumesucker Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 09:22 AM
Response to Reply #28
36. My understanding is that at high speeds the wings generate too much lift..
So they have to dial in down trim to kill the lift, if the trim goes away suddenly the aircraft pitches up unexpectedly.

I really haven't paid a lot of attention to this, I just happened to come across the picture while browsing news in general and the explanation in comments seemed pretty reasonable.

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The Velveteen Ocelot Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 09:51 AM
Response to Reply #36
38. The lift has to be balanced between the wings and the tail.
The tail produces downward lift so the aircraft pitches about its center of gravity in normal flight. If the downward lift produced by the horizontal tail surface is lost, the airplane pitches up abruptly. Depending on the aircraft, trim tabs are used either to control the elevator aerodynamically (in larger or high-performance aircraft), or just to adjust pitch trim. Considering the aerodynamic load on this aircraft at the speed it was flying, loss of the trim tab might have been enough to cause the loss of control.
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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 11:58 AM
Response to Reply #28
44. The P-51 was indeed designed for the airspeeds encountered at Reno.
The top speed at Reno for the unlimited class is in the neighborhood of 420 MPG.
This is a low altitude, flat course with high "G" TIGHT turns.

P-51s routinely exceeded 500 MPH in dives during WW2,
and some even approached the "Sound Barrier" (650+) in steep dives.


Upthread, it was stated that this accident happened just after Take Off,
and you can see in the photo that the Tail Wheel is still down.
(The Tail Wheel still being Down while the Main gear is fully retracted may be an indicator of other problems.)

In light aircraft with non-boosted, mechanical controls,
the Trim Tab is not a critical piece of equipment.
Flying & landing a plane with the Trim in full deflection (either way)
used to be part of the Older style of Pilot Training.
I learned from an old instructor, and had to do that.
It wasn't pleasant, but it also wasn't that difficult.
Flying with the Trim Tab in Full Deflection is much harder than flying without a Trim Tab at all.

In a properly rigged (control surface alignment), properly balanced aircraft, at cruising airspeed,
the loss of the Trim Tab will put the elevator in a Neutral position.
The use of any "trim" produces DRAG which costs fuel and airspeed.
Care is taken (or should be taken) to rig an airplane for neutral trim.

In a racing aircraft, the "trim" would be rigged (control alignment) neutral for top speed in order to avoid any unnecessary drag.
The pilot might not even notice the loss of the trim tab until he slowed down and tried to "retrim" for a slower airspeed.

If this crash occurred after take off (at slower speed) the pilot probably used some trim to compensate for the slower speed,
but losing the tab really shouldn't have been that much of a problem.
I believe the loss of the trim tab (and the tail wheel still deployed) to be an indicator of deeper structural problems.

Disclaimer:
I am NOT an Engineer, builder, owner, or pilot of Unlimited Racing Aircraft.
Everything I have written about this particular crash of this particular aircraft
has come completely out of my ass.

I am a life long Sport Flying enthusiast,
and obtained a Commercial License on my 19th birthday (1969).
I even have 1 hour in the jump seat of a modified P-51.





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The Velveteen Ocelot Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 03:26 PM
Response to Reply #44
54. Except that this P-51 was significantly modified from the original.
Edited on Sun Sep-18-11 03:27 PM by The Velveteen Ocelot
The wings were substantially shortened to make it faster and more maneuverable.

"In a podcast uploaded to YouTube in June, Mr Leeward said major changes were made to the plane before this year's race. He said his crew cut five feet off each wing and shortened the ailerons — the back edge of the main wings used to control balance — to 32 inches, down from about 60 inches.

The goal was to make the plane more aerodynamic so it would go faster without a bigger engine.
'I know the speed. I know it'll do the speed. The systems aren't proven yet. We think they're going to be OK,' he said."

The article also points out that the loss of the trim tab might have been caused by flutter, which can be catastrophic. Control surface flutter caused the crashes of a number of Bonanzas some years ago until an AD corrected the rigging problem.

In other words, the airplane was flying at very high speeds with unproven modifications. They reduced the wingspan by ten feet. That turns it into an entirely different aircraft from the one that flew in WWII.

http://www.dailymail.co.uk/news/article-2038749/Reno-Nevada-air-race-crash-WW2-planes-tail-missing-part.html

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bvar22 Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 05:29 PM
Response to Reply #54
58. Flutter IS a possibility at high speed, and could cause the trim tab to depart.
Edited on Sun Sep-18-11 05:46 PM by bvar22
The loss of the Trim Tab by itself is NOT catastrophic,
but can be an indicator of a more serious problem,
which I pointed out in previous posts.

I haven't watched the video, but a poster above stated that the accident happened shortly after take off,
and the tail wheel is STILL in the down position (from the photo),
so it is evident that the problem occurred before reaching speeds at which flutter is more commonly a problem.


Clipping the wings and tails is SOP for unlimited category racing planes,
and has been done to these planes for over 60 years years.
Every single plane in that race has had its wings and tails "clipped".
The pre-race inspections at Reno are very strict.
There are limits to what they will allow in this area.
Its not like the '30s when you could race anything you could get off the ground.

The armor, self sealing tanks, wing hard points (for bombs & rockets& external tanks),
guns, ammunition bays, extra gas tanks, oxygen equipment, and heavy radio gear have all been removed,
in addition to every single other piece of equipment not absolutely necessary for pure low altitude speed.
They don't need to carry near the amount of weight as their War Time configurations.
Therefore, they don't need near as much lifting surface.

Clipping the Wings is routine among sport aircraft, and actually makes the basic structure of the aircraft STRONGER.
The total load at the wing root is LESS with a shorter wing.
Many Piper Cubs have been transformed into High "G" aerobatic hot rods by "clipping" several feet from the wings.
These guys KNOW what they are doing,
but many have also paid the ultimate price.

I'll wait for the NTSB Report,
and will be deeply surprised if their conclusion is that the Trim Tab "falling off" caused this plane to crash.
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The Velveteen Ocelot Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 09:38 PM
Response to Reply #58
59. Check out this article: the modifications were radical and untested.
http://www.cbs8.com/story/15491307/plane-in-nv-crash-had-radical-changes-to-compete

But we will just have to await the NTSB's determination.
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 07:58 AM
Response to Reply #23
33. The seat is one-piece aluminum or carbon fiber. The seat back wouldn't break, It's not a car seat
Edited on Sun Sep-18-11 08:20 AM by leveymg
or anything like the seat in a Cessna. The standard P-51 seat is suspended from a steel frame with an armored plate back, like the one shown below. The racers do away with the heavy frame and bolt an aluminum or carbon fiber bucket seat to structural cross members under the floor. In both cases, there is little or no chance the pilot could flop backwards, out of sight. Even if the seat mounts failed, there's not enough room - behind the seat is a bulkhead that covers the fuel tank. There's only a few inches space behind the seat in a single-seat P-51.




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jberryhill Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 09:40 PM
Response to Reply #21
26. It's highly modified

And may be a lot less inherently stable than anything that ever met a Stuka.
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midnight armadillo Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 09:51 PM
Response to Original message
27. The pilot was 74. Maybe he had a stroke.
Or went into cardiac arrest.
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shanti Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 10:01 PM
Response to Reply #27
29. extremely possible
but will they ever know?
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CTyankee Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 09:37 AM
Response to Reply #27
37. I didn't want to say that but I did think that at first.
Aren't commercial pilots required to retire at age 60?

I say this being old myself. There are things I just don't attempt to do any more. I'm not disabled in any way, just older and my body and mind don't work as quickly as when I was younger. I am more ruminative and possibly wiser (or should be!) but that's not the important thing is flying acrobatically...
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applegrove Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Sep-17-11 10:35 PM
Response to Original message
30. I use to make paper airplanes with parts cut out of the tail like that. It would make the plane vere
violently up or down depending on which way the 'flaps' were folded.
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trumad Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 08:15 AM
Response to Original message
34. Great thread...
and one of the many reasons I'm still at DU.
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sfpcjock Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 11:31 AM
Response to Original message
42. It could be maintenance issues.
Older airplanes have more of them. The reaction might depend on which phase of flight the damage occurred in, I suppose.
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sgsmith Donating Member (305 posts) Send PM | Profile | Ignore Sun Sep-18-11 12:44 PM
Response to Original message
46. Pictures of Galloping Ghost during a 2009 tear down
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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 01:11 PM
Response to Reply #46
47. Thank you! Photo 7 clearly shows the top surface of the center section of the wing
Edited on Sun Sep-18-11 01:56 PM by leveymg
that's bolted from above into the notch on the fuselage (photo 21, and others). The center section of the wing-root is the same height as the rest of the top side of the wing surface. Go to the original site, as linked above, for a larger image.
http://lh6.ggpht.com/-n901d81ZPSc/Soy_zCkt1iI/AAAAAAAAAC0/3bUVZEqkDTw/s128/DH000007.jp

Also, photo 32 shows there's a bulkhead right behind the pilot on this plane. So, there's no way he stretched back, an explanation that some have offered for why his head is not visible in the final pre-crash photo set.

The cockpit floor is raised just a few inches above the center section of the wing root. The space between -- maybe 5-6"" -- has a bunch of pipes and cables running through it. Yes, the original P-51s had plywood floorboards, but they weren't structural. You can see that in a photo I found from another P-51 restoration, below. The Galloping Ghost fuselage appears to have been heavily modified with composites (or recreated), and I doubt there's any plywood in this one.

I still find it hard to believe the seat and floor dropped.

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leveymg Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-18-11 02:19 PM
Response to Reply #47
53. Photo 28 shows the front cockpit floor by the rudder pedals. Note the
Edited on Sun Sep-18-11 02:27 PM by leveymg
wing has not yet been inserted, therefore one can see through to the ground below. (Hit hide captions X button) If the cockpit is raised above the wing, it isn't by much on this particular P-51, which I would categorize as a recreation with few if any original parts. I now doubt even more strongly that the seat dropped.

http://picasaweb.google.com/jimmyleeward/GallopingGhost101909?authkey=Gv1sRgCLWz6b-lje6PKw&feat=email#slideshow/5371879921140891858
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