Witnesses speculated on other possible causes — a broken control wire, a snapped fuselage, a sudden downward movement of air, an attack of vertigo affecting the pilot, an abrupt foreward movement by the passenger. One news story noted: ‘There were many on the field who felt that Mr. Willard had no business to make such a flight under the circumstances. He had been under a heavy strain for months in getting up this meet. He was nervous and high-strung and his friends felt that it would be better for him not to make the flight… ‘

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The lack of proper seat belts was quickly seen as a factor. The Globe of July 2 said that Quimby, before taking off, ”had buckled a broad strap across a space in front of her’ and that this space ‘from the back of her seat to the strap measured slightly less than a foot:’ Nothing, strangely, was mentioned of such a strap in the rear seat. The reporter wondered how Quimby ‘could have been thrown from her seat without first unbuckling the strap.’ From today’s perspective, it seems clear that he knew little of the forces acting on the occupants of a fast-diving aircraft that makes such a sudden change in direction as apparently occurred in this case.

Incidentally, the reports of the time include no evidence that the Blériot pilots who had died in similar steep diveinduced crashes (John Moisant’s, for example) had been catapulted from their planes in midflight.

In its August 1912 issue, the magazine Aircraft, a leader in its field, devoted almost four pages to the accident. Included were articles by Walter H. Phipps on the Blériot’s dangerous instability, and Denys P Myers, who conceded the instability but agreed with Ovington that the main cause was jammed controls. Included also were reports from four key eyewitnesses — two favoring instability as the cause, a third (Ovington) who clung to his jammed-control theory, and a fourth who suspected a broken ‘forward truss wire’ under the wing, but offered virtually no proof.

Phipps’ article, ‘The Danger of the Lifting Tail and its Probable Bearing on the Death of Miss Quimby,’ had a convincing ring of fact. Phipps pointed out that the fixed horizontal tail surface of the two-seat Blériot was actually a small cambered wing, similar aerodynamically to the craft’s main lilting wing. A normal horizontal tail surface has a fixed, non-lifting surface for longitudinal (nose up or down) stability with a movable control surface, the elevator. Further, Phipps wrote, the tail surface was set at a higher lifting angle than the main wing to help carry the weight of a passenger who sat well back of the airplane’s center of gravity. His article, complete with photographs and drawings, showed how the combination of a lifting tail and the difference in angle created a situation of grave potential danger.

‘A machine of this type,’ he wrote, ‘has not the slightest degree of automatic longitudinal stability and … is an extremely tricky and dangerous type to handle. The horizontal tail should act as a stabilizing damper, preventing the machine from either diving too steeply or stalling and not under any circumstances as a lifting plane… it must be either a flat or slightly negatively inclined surface.’

The danger, he explained, is that if an airplane with a lifting tail is suddenly nosed downward (by a gust of wind or by negligence of the pilot), the tail gains in lift as the dive speed increases until a critical angle is reached. Then, he wrote, ‘it is impossible to get the tail down even though the elevator is pulled up…. The faster the machine dives the more the tail lifts (because it is set at a greater angle than the main plane) until the slight pressure under the main plane (wing) shifts to the top when the machine assumes a vertical position and throws the occupants out, unless, of course, they are strapped in.’

Phipps concluded with a litany of experienced pilots who had died in Blériot crashes. ‘The action of the lifting tail,’ he said, ‘probably explains the cause of the deaths of John B. Moisant, F Blanchard, Jules Noel, Rene Vallon, Valdemar, Kimmerling, W. Smith, Leforestier, Lieut. Edmond Boerner and others, all of whom were killed while attempting steep glides on lifting-tail machines.’

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