Submarines and their Weapons - Aircraft of World War II

SURFACE-TO-SURFACE MISSILES
Above: The preferred way to destroy the bombs from the
air was to tip them off course - not as risky a business as
one might suppose. The aircraft pictured in this gun
camera shot is, from its wingform, a Spitfire.
electro-mechanical all-ways fuze with a trembler
switch; and a mechanical (clockwork) delayed fuze.
The impact fuze had three actuators: one in the nose
and one in the belly (both of which functioned by
pressure); and an inertial switch in the fuze itself. The
fuzing system was so good that of the first 2500 to hit
the UK, only four failed to go off.
The launch system was less problematical than
other elements, and employed a simple steam catapult,
the steam being generated by the reaction of the
same T-Stoff and Z-Stoff (basically hydrogen peroxide
and calcium or potassium permanganate, as we
might recall) used in rocket motors. The catapult track
was a slotted tube 42m (138ft) long, inclined at an
angle of six and a half degrees (later, a track half that
length was employed), on a concrete and steel bed,
within which a dumbell-shaped free piston ran. The
piston incorporated a fin which protruded through the
slot in the tube, and engaged with a simple trolley on
66
which the missile sat. The slot was sealed by a tubular
strip which trailed behind the piston to be forced
into the slot by the pressure of the steam. The fuel to
generate the steam was contained in tanks on a trolley,
which also held the forged steel steam generation
chamber, secured to the rear of the launch tube by a
bayonet fitting. Alongside the rear of the ramp, there
was a starter unit which contained the equipment necessary
to get the pulse-jet operating.
LAUNCHING THE V1
The launch procedure was straightforward. The pulse
jet was fired up and allowed to run for seven seconds,
bringing it up to the correct operating temperature.
The valve on a large bottle of compressed air was then
opened by remote control, forcing 60 litres (13.2 gallons)
of T-Stoff and 5 litres (1.09 gallons) of Z-Stoff
into the steam generation vessel. Their reaction generated
a large volume of super-heated steam, and as
soon as the pressure in the chamber built up sufficiently,
a restraining bolt sheared, whereupon the piston
was free to travel up the tube, carrying launch
trolley and missile with it. By the time it reached the
end of the track - little more than half a second later,