Broken Mustangs

Jimmy Leeward and his Packard Merlin powered Mustang, Galloping Ghost

Fans of aviation and the families of the dead and injured are mourning the September 16, 2011 crash of Jimmy Leeward’s Galloping Ghost at the National Air Races in Reno, Nevada. Ten were killed including Leeward, and some seventy were injured.

I stress: Nobody knows the cause of the crash, and everything in this blog post is my own personal speculation.

The media has described Leeward’s plane as a “vintage” plane. This is hardly true. While WWII-era P-51 Mustangs, like Galloping Ghost, have long been mainstays of the Unlimited class in which he was competing, there is hardly a component of the original planes remaining. These planes are as fast and as modern as anyone knows how to make them. They are the fastest piston-driven airplanes in the world, and no expense is spared to gain a fraction of a knot in airspeed. Each is unique and is built to the extreme.

Leeward's broken trim tab

Attention focused early on a photograph of the tail of Leeward’s plane, showing a damaged trim tab on the elevator. This has happened to Mustangs before at Reno. In 1998, Bob Hannah was flying the P-51 Voodoo in a heat race and an elevator trim tab came off, causing an abrupt pitch-up which resulted in a 10 G deceleration that knocked Hannah unconscious. Fortunately he was able to land safely. Superficially, the situation appears very similar to what happened to Leeward.

Voodoo's broken trim tab

Aerodynamic forces are probably to blame for both breakages. When airplanes approach the speed of sound (Leeward and Hannah had both been traveling about Mach .67), airflow over certain parts of the airframe will exceed the speed of sound and create shockwaves. These can be like hitting the airplane with a hammer. They cause buffeting and damage.

Galloping Ghost showing deformation from tensile stress caused by high G loads (Note: This is an older picture and has no connection to the crash.)

Other photos show that Leeward’s tailwheel, which is normally retracted for racing, was extended. It’s possible that there was damage affecting multiple systems on the plane, but it’s perhaps more likely that the wheel could have popped out from a sudden high G load.

Leeward's helmet is forward of its normal position. (Nose of the plane is to the left, Leeward's helmet is light colored)

Leeward was able to radio a mayday call, alerting others to his problem, (Update – the NTSB said in its briefing that no mayday call was made, which makes more sense) but one photo of the plane just before its crash shows his helmet apparently leaning all the way forward against the controls. Leeward was 74 years old, and though he flew his Mustang at the edge of its performance envelope often, a 10 G shock might have knocked him out as it had to Hannah. At this time, nobody knows the order of events: the breakage to the trim tab, the mayday call, the extension of the tailwheel, and any potential aerodynamic force event.

It’s a major bummer for everyone involved. Hopefully this accident won’t impact the future of the race, but that’s another discussion for another time.

About Brian Dunning

Science writer Brian Dunning is the host and producer of Skeptoid.
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12 Responses to Broken Mustangs

  1. Cath Murphy says:

    What a tragic end to a long and successful racing career. My thoughts are with his and all the affected families. Hopefully the investigation will determine exactly what caused the accident and feed the findings into improving safety.

  2. Guy McCardle says:

    My heart goes out to all the victims and their families.

  3. Harry H Marsh says:

    Great article with great reasoning. My only clarification regards your claim of the tail wheel being lowered, yet you show a picture (of the Galloping Ghost showing tensile deformation) with no tail wheel to be seen. People should know this image is from previous shows; a simple Google search will provide images clearly showing the tail wheel is indeed lowered: http://www.msnbc.msn.com/id/44569068/ns/us_news-life/
    or here, image 10 of 23 (some great images):
    http://framework.latimes.com/2011/09/17/reno-air-races-crash/#/9

    A sad incident. Thanks for the great analysis.

  4. steve sinn says:

    I was at the race in 2000. I bought an old exhaust valve from a RR Merlin engine that was being offered for sale at a table near a Mustang sitting behind the table with old parts for sale. I do not know if it was Jimmy Leeward, but when I saw his photo it was a shocker because it reminded me of the man I bought the value from. Anyone know if he was there in 2000, and if he was was he
    selling parts?

  5. Michael Lynch says:

    My heart goes out to the families of Leeward and the others killed as well as to those injured in this accident. This is a HUGE loss to all of us!
    The one very relevant detail that you failed to mention regarding the Hannah accident was that Hannah’s P51 continued to climb to over 9000 feet, before the pilot regained consciousness. This gave Hannah enough time and altitude to regain consciousness, control and to land safely. The problem here is that Leeward was likely subjected to the same 10G’s and unfortunately, instead of climbing, the aircraft climbed, rolled over and plummeted to the ground. In the Hannah accident, the energy of the aircraft was absorbed in the climb to over 9000 feet. In the Leeward accident, the energy of the aircraft was released in the complete, horrific and deadly disintegration of the aircraft upon impact.
    While it is true that these aircraft are completely and meticulously rebuilt from mostly new parts, what has not changed, is the original design. It is likely that the trim tab mounting or actuator, whether old or new was, by design, subjected to stress, to which the materials used could not withstand. If this was a known problem, i.e. this had happened before, why was this problem not the subject of some sort of FAA bulletin or other document? What IS the threshold for problems such as this to be made know to all those involved with the affected aircraft? Or was this “common knowledge” in the Mustang racing community? If such a document or knowledge existed, it would be very relevant to this discussion.
    This is a well reasoned and insightful analysis of the accident. Unlike most of the media coverage, you have offered solid evidence to support what is a very likely scenario.

  6. Luis Barthel-Rosa says:

    Thanks for your post.

    Just a follow up on the the ‘MayDay’ call. The NTSB reported at their briefing on 9/18 that there was no ‘mayday’ call.
    The briefing is here, they discuss it at time indexes 1:37 and 13:12.

  7. Dan Pate says:

    The FAA may have not issued an “AD” (airman’s directive) for the trim tab failure when it occurred on Hannah’s P-51 in ’98. The reason being that these aircraft are designated as “Experimental” and basically one-off items, especially in the FAA’s eyes. Also, since in 1998 Hannah landed his plane with out incident, there was no accident for the NTSB to investigate. I could be wrong (as always).

  8. Jack Moss says:

    @Dan Pate
    AD is an Airworthiness Directive and compliance is mandatory. However, this aircraft is experimental and not flying under a Certificate of Airworthiness as an AD would apply to…

    Hannah’s incident would have been reported as an incident and I am sure that every air-racer would be aware of the incident. It does not have to be an accident before the NTSB will investigate.

    The modified cooling system meant that the Ghost would have been carrying a large amount of water on board which would have tended to extinguish any fire on impact. Leeward had removed the original cooling radiator to reduce drag, with a system similar to that fitted to the other aircraft that had a similar incident, the Voodoo Air racer. This system uses a large water and methanol tank that acts as a heat exchanger for the coolant and oil systems. As the system heats up, the water in the tank boils off, leaving the trail of steam you can see in the images. This system would be operating nominally by the end of this event and some steam would be visible.

    What ticks me off is when people state that this is an old aircraft flown by an old man. These are the trickest, fastest propeller driven aircraft in the world. Their design almost reached the state of the art some sixty years ago, with incremental advances in speed over the last six decades.
    Leeward would have had a lot to live for, being a successful business man in the golden years of his life. He solo’d his first aircraft at 14 and has been flying all his life.

    I think the tab broke, he pitched up, G-LOC’d and broke his seat pan, gyroscopic precession rolled him over and the throttle stayed wide open to the impact.
    Rmember the old adage:

    “There are old pilots or bold pilots. There are NO old bold pilots”

  9. Dan Pate says:

    I stand corrected on the terminology regarding an AD. I was just throwing some thoughts out to be processed. I tend to agree with the hypothesis: separated trim-tab > pitch up > high G load > G-Loc > high speed encounter with terrain.

    I’m very certain there is a large amount of data that the NTSB has that we are not currently privy to. I’m very confident that they will determine the cause with a high degree of accuracy.

    I’m also very confident that Mr. Leeward would have done “everything” in his power to keep his aircraft from putting anyone’s safety in jeopardy if he was given the opportunity. However, I don’t think he was conscious from the point of the pull-up on.

  10. Tony G says:

    Both aircraft had ”clipped wing” mods reducing the main wingspan , speculation but I’m figuring this mod is putting the elevator and trim tab in a slightly different attitude to normal and perhaps under more load and stress

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