The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

416
John Paul Stapp (1910–1999)
An American pioneer of aerospace medicine,
famous for his extreme rocket-sled experiments.
Stapp was born in Bahia, Brazil, 1910, the son of
Southern Baptist missionaries. At age 12, he moved
back to the United States with his family and later
started college in Texas with the idea of becoming a
writer. During Christmas vacation 1928, he witnessed
a tragedy that changed his life. While he was visiting
relatives, his baby cousin crawled into a fireplace and
was badly burned. For three days before the child
died, Stapp helped nurse the child; afterward he determined
to become a doctor. Fifteen years later, having
earned degrees in zoology and biophysics, he entered
the University of Minnesota medical school to pursue
his dream. When he graduated, he interned at St.
Mary’s Hospital, Duluth, before enlisting in the Army
Medical Corps during World War II.
In 1946, Stapp joined the aeromedical laboratory at
Wright Field and was serving as flight surgeon to
Chuck Yeager when he broke the sound barrier. Stapp
became convinced that a significant pattern lay behind
the way some airmen died and others survived seemingly
equally violent crashes. To solve the mystery, he
used a high-speed rocket sled at Morocco Air Base.
Stapp planned a series of tests on humans and set
out to develop a harness to hold them safely to the
rocket-powered sled, known as the “Gee Whiz.” First,
he used a dummy named “Oscar Eight-Ball” to perfect
the harness. Finally, after 32 sled runs, he was
ready to try it out on a human guinea pig—himself. He
was strapped into the sled facing rearward, refusing
anesthetic because he wanted to study his reactions
first-hand. Accelerated almost instantly to 145 km/hr
(90 mph), Stapp was then crushed against the seat
back as the sled ground to an abrupt halt. He suffered
only a few sore muscles. Within a year, Stapp had
made sled runs at up to 240 km/hr (150 mph), stopping
in as little as 5.8 m (19 ft). He experienced up to
35 times the force of gravity (35g) and proved that the
human body could withstand such stress, although in
the process he suffered headaches, concussions, a fractured
rib and wrist, and a hemorrhaged retina.
When Stapp’s commanding officer learned he’d
been his own test subject, he ordered the experiments
to stop, fearing he’d miss out on promotion if Stapp
were killed. However, Stapp secretly continued the
tests, using chimpanzees, and found that when
strapped in correctly they survived forces many times
those experienced in most plane crashes. From this, he
concluded that crash survival doesn’t depend on a
body’s ability to withstand the high forces involved,
but rather on its ability to withstand the mangling
effects of the vehicle. To back up this idea, Stapp again
unofficially began tests on humans—putting himself
first in the firing line. Over the next four years, he lost
fillings, cracked more ribs, and broke his wrist again.
Yet, despite these daredevil exploits, Stapp was known
as a quiet, philosophical man who loved classical
music. He refused to marry until his test days were over.
In 1949, Stapp was involved in the birth of Murphy’s
Law. Stapp’s harness held 16 sensors to measure
the g-force on different parts of the body. There were
exactly two ways each sensor could be installed, and it
fell upon a certain Captain Murphy to make the connections.
Before a run in which Stapp was badly
shaken up, Murphy managed to wire up each sensor
the wrong way, with the result that when Stapp staggered
off the rocket sled with bloodshot eyes and
bleeding sores, all the sensors read zero. Known for his
razor-sharp wit, Stapp quipped: “If there are two or
more ways to do something and one of those results in
a catastrophe, then someone will do it that way.”
The advent of supersonic flight and the need to bail
out at very high speed demanded more extreme experiments.
Transferred to head the aeromedical field lab
at Holloman Air Force Base, New Mexico, Stapp built
a much faster sled, called “Sonic Wind No. 1.” Again,
he began his studies using dummies, but in March
1954, he put himself forward as the subject. In his first
ride on the new sled, Stapp reached 677 km/hr (421
mph)—a new land speed record.
On December 10, he took the sled chair for his
final and most extreme ride. His wrists were tied
together in front of him, because flapping limbs
would be torn away in the ferocious air stream. His
major concern was that the rapid deceleration might
blind him. Earlier he had “practiced dressing and
undressing with the lights out so if I was blinded I
wouldn’t be helpless.” At the end of the countdown,
Stapp was shot to 1,002 km/hr (623 mph) in 5 seconds
and back to rest in just over a second. Subjected
to 40g, he temporarily blacked out, and his eyeballs