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

mustpost 18th Sep 2011 18:39

John Farley, thank you for your erudite comments here (and some others as well.) Much appreciated.

jumpseater 18th Sep 2011 18:48


One might also question the likelihood of someone being able to capture such a sharp image of an unplanned event.

Also, most photos shown in media outlets portray the aircraft as moving from left to right (i.e. undercarriage towards the left of the image), this photo is the opposite.


Well I don't question the likelihood at all. Then again people sometimes ask me to take images and I understand how to take pictures, and how to work a camera.

The guy was assigned to shoot the event so the chances of him submitting a photoshopped 'moneyshot' like this with worldwide sydication to news media, is about as unlikely as you working out where he was positioned to take it. To do that would be the fastest way of assuring you never get any work again. The only thing second to the number of armchair accident investigators when these sorts of event occur, is the number of armchair professional photographers it brings out.

Flight Safety 18th Sep 2011 18:58

Adequate Testing
 
Given the description of the 1998 event, I wonder if there's adequate testing of these aircraft after modifications have been made to the airframes. Given that the purpose of the mods is to increase airspeeds at low race altitudes (i.e. dense air), surely flutter testing would have to be part of ANY test regime following these modifications. Surely this testing needs to be completed prior to ANY racing in front of grandstands.

I apologize if this has been asked and answered already, but do we know if any significant modifications were made to this P-51 just prior to this race?

mixture 18th Sep 2011 19:26

jumpseater,


is the number of armchair professional photographers it brings out.
Take a chill pill.

I will repeat again what I said, with extra bold for emphasis.



But I'm staying neutral, as it might just be a case of "right place, right time" (plus right camera, right lens, right photographer !).


Spit161 18th Sep 2011 19:44


Underside of that wing looks pretty well-lit for an aircraft which is supposed to have been photoshopped on the ground, when the underside would be in shadow...
I agree.
I say it is just a trick of light/right place, right time.

Lyman 18th Sep 2011 20:07

On the ground, almost invariably, the Propellor is in flat Pitch, not High.

Thinking that is the real deal.

jumpseater 18th Sep 2011 21:31

Well mixture, yourself and LIS suggesting its photoshopped are talking out of your holes. A simple compare and contrast with other images and video of the event elsewhere will show other photographers images with 'no pilot'. So unless theres a secret Jane-Doh type conspiracy that every snapper there colluded, via the every snapper knows every one else network, to all remove the pilot from their images, stills and every single video still image, theres a pretty good chance wysiwyg.


The guy who took that image was on assignment. So, right time, right place, right equipment, right settings, right skillset, right awareness, right image cropping, etc etc. But no, wait, it may be photoshopped and heres a whole list of ill thought out reasons for you to disregard, subject to doing a minutes thinking. I now await the 'disgust bus' to arrive full of complainers that the pro snapper was paid for taking these images, that are now being used to discuss the accident ...

Passenger 389 18th Sep 2011 22:50


I apologize if this has been asked and answered already, but do we know if any significant modifications were made to this P-51 just prior to this race?
@Flight Safety. Post #67 references some changes through June 2011.

AP also has story on the wire entitled "Plane in NV crash had 'radical' changes to compete" -- though bear in mind how accurate the media can sometimes be on aviation issues.

News from The Associated Press

the snapper 18th Sep 2011 22:54

Hi Guys
I'm new to this forum and have been reading all the posts regarding this
horrific and tragic accident.
Judging by some of the comments posted by some of the forum members
i can only pressume they have their minds made up on all the different theories and reasons as to what may have caused the crash in the first place.
My personal views on the whole scenario are,
1. The pilots age would IMHO have made no difference whatsoever to the
outcome,if a trim tab breaks of at the speed that he was travelling at and
especially when he's least expecting it the pitch up from level flight to near vertical would have induced some serious g-forces which probably and surely would cause blackout almost immediately.
2. These guys that race these planes do modify them and spend huge bucks doing so, obviously they have to operate them to a standard that allows them to fly them at their limits,where as in Europe the build them and fly them for authenticty and for everyone to see them as they were
in whatever theatre they flew in way back when.
3. When involved in,let it be road racing,bikes or cars,flying, let it be racing
or displaying risks are high.Anyone who partakes in any of the above know
the risks and know when and when not to cross the boundaries.We as spectators know the risks to and unfortunately for those involved in Reno
the unthinkable happened.
And finally lets hope that this tragic event won't put an end to a brilliant
show that really shows the work and effort put in by the pilots,crews and organisers of truly one of the greatest flying spectacles in the world.

FoundationMetro 18th Sep 2011 23:10

Where did you get the picture looking down at the aircraft?
 
I would really like a high resolution of that shot. I've downloaded the one you put up but the resolution is such that it will not allow me to zoom into the detail I would like to see. Thanks

Pilot DAR 18th Sep 2011 23:38

I speak as a person who knows next to nothing about the regulations which apply to the modification and racing of warbirds. I also know very little about P-51's. However:


surely flutter testing would have to be part of ANY test regime following these modifications. Surely this testing needs to be completed prior to ANY racing in front of grandstands.
Gosh, I hope so, But I wonder...

These intrepid aviators invest fortunes in these aircraft to get every knot of speed out of them. That obviously involves modifying them. Were it to be a certified aircraft, there would be very specific criteria to which the modified aircraft would have to demonstrate compliance - by test flight.

I'm guessing that's not the same in respect of these racing planes (but I don't know for certain). I'm imagining a fellow with his pride and joy super fast modified warbird, going to the races to wring every knot out of it he can. I'm not imagining that he takes the plane to the races and says: "Yep, here are the flight test results demonstrating a flutter margin up to 550 knots, so I'm going to fly the course at exactly 500 knots, so the margin of safety is there for everyone. I'm not passing judgement either way, I'm just guessing that it's just different from certified flying most of us know.

Most of us get in our beloved and equally maligned "spam can", see a red line on the airspeed indicator, and think to ourselves: "Gawd, I can't imagine having the nerve to even take it that fast!". Be assured that model has safely flown faster. Every aircraft I flight test, I fly to 110% of the red line speed, as required by the design requirements. This is of course done in accordance with a flight test plan, under the terms of an experimental flight permit. But it is done so that when someone goofs in the cloud, rolls it over and pulls through, they are safe, if they don't fly it past the red line (and don't over stress it). Try to imagine how far the nose has to be put down to get a Citabria float plane past red line! It's not going to happen by accident! On the other hand, you can get a Caravan or Navajo through fairly easily....

The military back in the day subjected the P-51 to intensive flight testing, and I'm sure there's lot's of data out there. But from that, I'm betting that they established appropriate limitations, and red lines. When you start clipping wings, adding power, and flying it extra fast, it's no longer a P-51 out of the box, it's a new plane, with a lot of P-51 parts in it. Things can be different.

None of this is intended to portray the racers in a poor light. I'm confident that they apply the resources needed to produce a plane which is appropriately safe. I would if I had that much invested! They know they have the design standards to fall back on, if they need guidance for the modifications.

I'm just having trouble imagining the same margins (110% for speeds, or factors of safety of 1.5 to 2) between "proven during testing" and "flown in service" that we are used to with certified aircraft.

I wish the racers safe and happy flying (and little regulatory interference), I am in awe of what they do. More than in a lot of corners of aviation, I trust that they do things carefully, and well. But, I also think they are probably flight testing around those pylons too...

Oakape 19th Sep 2011 00:17

Looking at the photo on the left in post #111, there appears to be a white sphere in the windscreen (forward portion of the canopy).

Is this likely to be part of the aircraft equipment or is it possible that it is the pilots helmet, giving weight to the theories posted earlier in this thread that the pilot has been forced forward due to the 'G' forces experience in the pull-up?

M609 19th Sep 2011 00:33

The high res version

http://www.middletownpress.com/conte...2920201166.jpg

BreezyDC 19th Sep 2011 01:47

Two points:

1. Note the photo is copyright, and should always be posted with credit to the photographer: AP photo/Grass Valley Union, Tim O'Brien (MANDATORY CREDIT Photo: AP / AP) . I'll leave it to others to judge whether these postings and reuse of the photos without license payments falls under fair use.

2. For the Photoshop conspiracy theorists, a video interview with the photographer is at

westhawk 19th Sep 2011 02:07

Updated Information:
 
CNN.com today provided some updated information regarding the Reno crash. Here is a link to the story. I have no idea how long the link will last.

I'll summarize what I believe to be the interesting parts related to understanding what happened.

NTSB board member Mark Rosekind, PHD (some of you might be familiar with his work in pilot fatigue research) announced that a telemetry system was installed aboard the accident aircraft and that NTSB personnel have been provided with the received data stored by the ground crew. Information regarding which specific parameters were recorded was not detailed in the briefing. A video cam was also installed. Multiple data memory cards were recovered from the wreckage and sent to the NTSB lab for analysis. The origin of these memory cards is unknown. Some may be from devices carried by spectators.

Rosekind was also quoted as saying that no mayday call was received from Leeward.

Parts of the tail section have been recovered including the detached trim tab.

It was also noted that a tremendous amount of video has been provided for investigators for analyze.

Analysis to follow.

tartare 19th Sep 2011 03:27

Course layout at Reno
 
A question - having never been to Reno, I am attempting to understand the layout of the racecourse, relative to the crowd.
From the charts that I can find online, it appears the unlimited course `front' and `back' straits (for want of a better term) both face toward the main grandstand/viewing area.
If I am reading these charts correctly, would it be possible to rotate the racecourse by 45 degrees, meaning that aircraft were flying at highest speed parallel to the viewing area, instead of straight at it?
Or are the terrain issues - I see hills in the background of much of the videos.
I'm pretty sure that post the Ramstein airshow crash, manouveres towards the crowd were prohibited.
I guess at 400+ knots, any distance of less than a mile from the course to the crowd is purely academic if there is a loss of control.
An awful accident - but it would also be a terrible shame if this event was brought to an end.
The engine and air-frame noise from those aircraft and the sight of them is awe-inspiring...

westhawk 19th Sep 2011 04:35

My take on things:
 
First I'd like to say how badly I feel that spectators were injured and killed in this accident. As someone who barely escaped a similar fate at Flugtag '88 and saw my share of disturbing sights, I have nothing but sympathy for all those affected.

That said, I have an interest in analyzing and understanding the events that take place in aviation and this event is no exception. As a pilot, aviation mechanic and long time race fan who has attended 15 of the last 20 race years, I have more than a passing interest in this accident. To the "don't speculate, wait for the report" gang: Sorry, no dice. Well reasoned discussion of a technical nature is a different thing than wild uninformed speculation. Trouble is, only technically savvy people with good reasoning skills seem to recognize the difference!

My own analysis of the information available to me as of this date comes with the proviso that it is only a working theory and subject to modification by new facts or correction of any flawed theories or assumptions. We're not gonna hear much substantial analysis from the NTSB for quite some time. Consequently, I feel that some reasonable speculation among the more informed participants having a factual and/or supportable theoretical basis for their ideas is more constructive than might otherwise be proffered if these ideas were not offered for the purposes of discussion. So here goes my take on what's apparent so far:

Photos indicate that the trim tab on the left elevator became partially detached then departed the aircraft at some point in the sequence of events. It is logical to presume that the detachment of the trim tab would cause a significant change in elevator hinge moments and therefore the elevator control forces.

At very high airspeed, the trim would typically be adjusted pretty far in the nose down (tab T/E up) direction to counter the airplane's natural nose up tendency with increased airspeed. Removal of the trim tab induced force about the elevator hinge point would result in a significant change in the control force required to hold the elevator in the desired position. I would expect that an immediate and strong elevator trailing edge up (stick back) force would result from the loss of the trim tab under this condition of high speed flight.

When added to any force already applied, the gees could reasonably be expected to build faster than the human can react to apply forward stick before the onset of gee induced loss of consciousness. (As happened to Hannah in '98) What video of the sequence I've seen appears to indicate a rapid upward change in flight path somewhere west of the pits approaching the home pylon. At 500 mph, that rate of angular change certainly appears to me to be indicative of some pretty high "G" forces. Why Hannah's plane continued skyward and Leeward's rolled into a dive is open to conjecture, but that's the difference in outcomes it seems.

The video and still images seen so far appear to support the theory that the pilot was rendered unconscious during the pullup and exerted no control after that. Had the airplane not been rolling as well as pitching, there might have been more time for a recovery such as Bob Hannah's, but we'll never know.

I'll be interested to see if the NTSB opens a public docket so we can access some of the investigative work product prior to release of the final report as has been the case in many major accidents. The possibility that they may have some recorded flight parameters is intriguing will hopefully include good time reference, attitude and/or accelerometer data.

westhawk

westhawk 19th Sep 2011 05:01

Course Layout
 

Originally Posted by tartare
A question - having never been to Reno, I am attempting to understand the layout of the racecourse, relative to the crowd.

Yes, the terrain is one feature determining the present layout of the unlimited course. The existence of some housing does as well. The "dead line" or no transgression zone is aligned roughly parallel to the East/West runway as are the grandstands. The airplanes ground track is normally oriented parallel with or slightly away from the crowd by the time they are in front of the pits, west of the grandstands. In this case it appears that the detachment of the trim tab and subsequent pitch up occurred just as the airplane was completing the last turn and continued across the dead line in a climb, then rolled into a dive, impacting the VIP box area on the ramp. (apron in ICAO-speak)

It would be nice if aterpster or another of our map gurus would come along and post a relief map with the course layout superimposed. I'll check out MAPS and see if a decent view is possible there.

tartare, I suspect your suggestion of reviewing the layout will be one of the things race officials, the NTSB, FAA and other concerned parties will be looking at too.

westhawk

sitigeltfel 19th Sep 2011 07:12

Ignorant Journos strike again, this from the Torygraph....


They also said they had found no indication yet that the pilot of the plane sent out a distress call before his sleek silver jet plunged nose-down into the tarmac.

MichaelJP59 19th Sep 2011 08:41

Looking at the crash video posted above, if the speed is about 500mph and the time from horizontal flight to vertical is about 2.5 seconds a back of the envelope calculation suggests approx 15g initial G!

On a personal note, I've never been to Reno but have been fascinated by the unlimited air racers for years. I hope that the community recovers from this tragedy and also hope to get to see them one year.


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