The Father of Crash Investigation

In 1908, Frank Lahm issued the first airplane accident report.

Bystanders crouch over Thomas Selfridge, pulled from the wrecked Wright Model A. (Library Of Congress (ds-01202u))
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While riding as a passenger in a willowy, wing-warping biplane piloted by Orville Wright, U.S. Army First Lieutenant Thomas Selfridge became the first person to die during powered flight. Even before the debris was cleared away, First Lieutenant Frank Lahm began investigating the wreck. Five months after the incident, Lahm issued the world’s first airplane accident report.

Orville Wright had thrilled military officials by setting world records over Fort Myer, across the Potomac River from Washington, D.C.

On September 17, 1908, more than 2,000 spectators flocked to watch Wright fly with Selfridge, who just four months earlier had become the first Army officer to fly an airplane. The Wright Model A was the most technologically advanced airplane in the world, and Wright had just replaced its two eight-foot, eight-inch diameter propellers with nine-foot ones to make the aircraft faster. Selfridge could hardly restrain his enthusiasm. He waved his cap vigorously at the crowd beneath him and could be seen talking animatedly to Wright as they completed three circuits above the field.

At a speed of about 40 miles an hour and an estimated altitude of between 100 and 150 feet, Wright heard “a light tapping” behind him. He whirled around and saw nothing wrong, but, as he later wrote to his brother, soon felt “two big thumps, which gave the machine a terrible shaking.” The airplane corkscrewed right and pitched up—“rock[ing] like a ship in rough water,” one observer recalled—then nosed almost straight down. About 25 feet from the ground, the airplane began easing out of the dive. “A few feet more,” Wright wrote, “and we would have landed safely.”

The skids dug into the ground, and the airplane crashed “with frightful force,” a newspaper reported. Wright was quickly pulled from the wreckage, dazed from the pain of broken bones. But it took several minutes to free the unconscious, bloody Selfridge. He died in surgery about three hours later, the victim of a skull fracture.

Lahm was the obvious choice to conduct the War Department-ordered investigation. He’d flown with Wright a few days before the accident, had seen the crash, and had helped drag Wright from his mangled airplane.

Lahm interviewed about a dozen spectators, from an artilleryman who, Lahm later wrote, “gave the impression of being a reliable witness” to Octave Chanute, one of the foremost aviation theorists of the day. Several of them verified what Lahm himself had seen: a chunk from one of the propeller blades break off during flight and fall to the ground. Lahm found and examined the broken propeller, and took precise measurements at the scene.

Wright was so distraught that Lahm wasn’t able to question him for several weeks. Based on Wright’s recollections and the physical evidence, Lahm’s conclusion was that the broken propeller had caused damage that rendered the airplane uncontrollable.

“I am of the opinion that due to excessive vibration, this guy wire [securing the front rudder] and the right hand propeller came into contact,” Lahm wrote in his report, issued on February 19, 1909. “The clicking which Mr. Wright referred to being due to the propeller blade striking the wire lightly several times, when, the vibrations increasing, it struck it hard enough to pull it out of its socket and at the same time to break the propeller.”

The next summer, Wright returned to Fort Myer with an upgraded Model A. With Wright serving as his instructor, Lahm learned to fly in this airplane, and became America’s second certified military pilot.

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