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Feature Article: Spins Were A One Time Thing In 1914
An unheralded aviation pioneer is British scientist, F. A.
Lindemann. "The Prof", as he was known, led a very
checkered scientific and social career from early WWI through
WWII. He was an "idea man" and advisor to Churchill
for thirty years. He was a social butterfly and a scientific
gadfly in the opinion of more capable scientists. However, his
place in history could well lie in aviation and you never heard
of him?
Born of German/American parents, he spoke heavily accented mumbled
English. He knew all the "right" British nobility and
used their influence to gain both position and prestige. In 1914
he attempted, but failed because of eyesight, to join the Royal
Flying Corps. He then used influence to join the scientific staff
of the Royal Aircraft Factory.
In 1914 the "spin" was the most dreaded unintentional
flight occurrence which resulted in accidents. More to be feared
than the more frequent landing accidents. At least, landing accidents
could be explained. Once an aircraft was in a spin there was
no way out of it. The spin turns would increase in speed until
the ultimate crash. All flight instructors warned, "Get
into a spin; get killed". Lindemann initiated a study of
the instrument readings and pilot procedures that seemed to cause
the stall/spins occurring during turns.
A letter to his father said, "Nobody can make out quite
what happened." Lindemann could find no apparent pattern
as to when a stall or a resulting spin might occur. A British
naval pilot was said to have recovered from a spin. If not known
if Lindemann used this event to develop an explanation, a theory,
about spins. While never publishing his study results, Lindemann
gave many oral accounts of his findings.
The spin frequently occurred when the aircraft stalled in other
than an absolutely level condition. If one wing dropped any effort
to raise it would cause the other wing to flip over uncontrollably.
Even at high speeds, a tight turn might cause one wing to flip
over and cause a spin. Without any flight skills, Lindemann had
worked out in theory the probable forces which, caused and existed
in a spin. He also figured out, in theory, the control movements
required to counteract these forces.
His study showed that any instinctive response would not work.
The rudder must be held fully against the spin while the nose
was kept pointed toward the ground. You could not pull back on
the stick until the spin stopped and flying speed was gained.
His theory also seemed to indicate that during the recovery the
wings of the plane could be pulled off. The way Lindemann used
to test his theories was somewhat akin to a medical researcher
doing a self-inoculation for a deadly disease.
He insisted that further study to prove the theory required that
scientists fly. He worked through and around the bureaucracy,
used influence, memorized the eye chart for his "blind"
eye and learned to fly "poorly". One 1914 flight of
uncertain date justifies Lindemann's place in history. One Fall
day, he discussed his theories on spin recovery and the planned
experiment with observers at Farnborough Aerodrome. He would
be using a B.E.2 aircraft of most uncertain flight characteristics.
The fragile airframe was held together by a maze of wires and
struts that maximized a power off vertical speed of about 90
mph. He told them he was planning to do a deliberate stall spin.
He certainly must have said his good-byes. He departed and climbed
for many minutes. Far below, the observers saw him reach what
must have been the B.E 2's service ceiling of 14,000 feet. They
saw the spin well before they heard the cessation of engine noise.
Lindemann now began to test his theory. He pulled the power,
slowed the plane and entered into a stall. He held the stall
until the left wing dipped and the right wing flipped up for
the spin entry. A deliberate entry into a maneuver from which
no one had previously recovered and few had survived. A maximum
test of accountability and courage.
Lindemann held the spin, intentionally or otherwise, until it
was fully established and then he initiated his unique recovery.
A deliberate application of control forces never before applied.
He put in full opposite rudder. Nothing happened. He waited.
Still nothing happened. He applied forward control pressure.
He had already fallen thousands of feet with no control effect
discernible. Was his theory going to fail at this critical moment?
But the rudder was starting to have an effect. The spin was slowing
and finally stopped. From the vertical, but without the spin
Lindemann now had to complete a recovery. Survival demanded that
the pull out would not remove the wings from the fuselage. Slowly,
carefully the nose rose and as it rose the aircraft slowed thus
easing the stress on its components. The first intentional spin
and recovery. All that and survival. Enough?
One such experiment and proof would have satisfied most people,
but not Lindemann. He climbed back up to altitude and did the
spin and recovery in the other direction. A theory twice applied
and proven to be a life saver. From that day on, a pilot's education
has not been deemed complete without spin training. (Except,
of course, in the U.S. by the FAA).
The British had a military secret. It combined two of the very
best qualities of military combat. Deception and survival. A
British pilot, when out-numbered or fearing for his life, could
deliberately enter a spin. To the enemy such a maneuver was not
survivable. The Germans would circle and wait for the inevitable
crash of their `kill'.
Imagine their chagrin, when the British plane would level out
close to the ground and scoot to safety. Indeed, the spin was
often used in WWI as a deliberate escape maneuver. It wasn't
long before the Germans discovered the deception and began to
follow spinning planes all the way to the ground. It is not known
how the Germans gained the secret of spin recovery. Pilots are
known to brag about their flying exploits while talking flying
with other pilots.
Most great aircraft flights recorded in aviation history are
about distances, speeds and kills. Why not a special "save"
category for Lindemann along with Immelman? But again, wouldn't
your entering his name into your memory and applying his theory
and practice to your own "Lindemann" spin recovery
be sufficient.
An aside: In WWII Lindemann served as Churchhill's scientific
advisor. He stood alone against all other British scientists
in his contention that the greater military potential lay in
infra-red than in radar. He lost the contest in WWII and radar
saved Britain. In 1990, Lindemann was partially vindicated. Desert
Storm would not have been possible without infra-red. A little
known man of his time and ahead of his time.
Last Modified September 19, ©2021 TAGE.COM
