"Pykrete" was first developed in 1943
Cold Research Laboratories by scientists working under
. These researchers created a
mixture of between four and fourteen percent wood
in water. The slushy mixture was frozen into a
material first named piccolite. Later it became known
Testing of this material showed astonishing strength.
The crush resistance of clear ice is between 250
1,300 PSI, but pykrete's
resistance proved to be more than 3,000 PSI. The wood
pulp appeared to insulate the
pykrete, making it considerably more stable at high
temperatures than ordinary ice. A small expenditure of
energy would keep it frozen.
Pyke's "Habbakuk memorandum" came up with several
cockeyed ideas. The most famous one involved a giant
aircraft carrier made completely from pykrete. This
theoretical ship would have been two thousand feet
long and would have had a thirty-foot-thick hull.
Pykrete's specific gravity was found to be lower
than that of ice, and this meant that an ocean-going vessel
made of the substance would be almost unsinkable.
The maximum speed of such an ungainly vessel would be
severely limited, but because of pykrete's
invulnerability this would not matter in a combat
environment. Calculations suggested that if a vessel
of this type were hit dead on by a torpedo, the
blast would produce a crater only three feet deep and about
twenty feet in diameter. This damage would be almost
unnoticeable on the vessel's thirty foot thick sides.
Pyke and his team suggested that this iceberg aircraft
carrier could survive waves one hundred feet high, and
that incendiary attack would hardly damage them.
This vessel's innards were to contain
plants, workshops, hangars and living areas. Their
runways would launch any military aircraft then in
use. Each iceberg aircraft carrier would contain
sufficient fuel for a seven-thousand-mile non-stop
cruise. Pyke suggested that freezing units could
circulate cold air throughout cardboard tubes, frozen
into the pykrete. This would, he theorized, keep the
ship from melting. Cork sheathing was suggested to
protect the exterior of the ships against possible
Despite sounding like complete lunacy to modern
ears, the idea was actually very positively received
by both Lord Mountbatten (Chief of Combined
Operations) and British Prime Minister Winston
Churchill. They envisaged it as a way to close the
"air gap" over the Atlantic Ocean by providing a
near-indestructable mobile launch platform for air
operations. A 1000-ton test ship made of pykrete was
actually built in a lake in Alberta, Canada. It
withstood impressive amounts of strafing and
bombing, but the project was ultimately cancelled
and the prototype destroyed.
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