The Birth of the
Checklist.
On
October 30, 1935, at Wright Air Field in Dayton, Ohio, the U.S. Army Air Corps
held a flight competition for airplane manufacturers vying to build its
next-generation long-range bomber. It wasn't supposed to be much of a
competition. In early evaluations, the Boeing Corporation's gleaming
aluminum-alloy Model 299 had trounced the designs of Martin and Douglas.
Boeing's plane could carry five times as many bombs as the Army had requested;
it could fly faster than previous bombers, and almost twice as far.
A
Seattle newspaperman who had glimpsed the plane called it the "flying fortress,"
and the name stuck. The flight "competition," according to the military
historian Phillip Meilinger, was regarded as a mere formality. The Army planned
to order at least sixty-five of the aircraft.
A
small crowd of Army brass and manufacturing executives watched as the Model 299
test plane taxied onto the runway. It was sleek and impressive, with a
hundred-and-three-foot wingspan and four engines jutting out from the wings,
rather than the usual two. The plane roared down the tarmac, lifted off
smoothly and climbed sharply to three hundred feet. Then it stalled, turned on
one wing and crashed in a fiery explosion. Two of the five crew members died,
including the pilot, Major Ployer P. Hill (thus Hill AFB, Ogden,
UT).
An
investigation revealed that nothing mechanical had gone wrong. The crash had
been due to "pilot error," the report said. Substantially more complex than
previous aircraft, the new plane required the pilot to attend to the four
engines, a retractable landing gear, new wing flaps, electric trim tabs that
needed adjustment to maintain control at different airspeeds, and constant-speed
propellers whose pitch had to be regulated with hydraulic controls, among other
features.
While
doing all this, Hill had forgotten to release a new locking mechanism on the
elevator and rudder controls. The
Boeing model was deemed, as a newspaper put it, "too much airplane for one man
to fly. The Army Air Corps declared Douglas's smaller design the winner. Boeing
nearly went bankrupt.
Still,
the Army purchased a few aircraft from Boeing as test planes, and some insiders
remained convinced that the aircraft was flyable. So a group of test pilots got
together and considered what to do.
They
could have required Model 299 pilots to undergo more training. But it was hard
to imagine having more experience and expertise than Major Hill, who had been
the U.S. Army Air Corps Chief of Flight Testing.
Instead,
they came up with an ingeniously simple approach: they created a pilot's
checklist, with step-by-step checks for takeoff, flight, landing, and taxiing.
Its mere existence indicated how far aeronautics had advanced.
In
the early years of flight, getting an aircraft into the air might have been
nerve-racking, but it was hardly complex. Using a checklist for takeoff would
no more have occurred to a pilot than to a driver backing a car out of the
garage. But this new plane was too complicated to be left to the memory of any
pilot, however expert.
With
the checklist in hand, the pilots went on to fly the Model 299 a total of 18
million miles without one accident. The Army ultimately ordered almost thirteen
thousand of the aircraft, which it dubbed the B-17. And, because flying the
behemoth was now possible, the Army gained a decisive air advantage in the
Second World War which enabled its devastating bombing campaign across Nazi
Germany.
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