Submarines and their Weapons - Aircraft of World War II

ROTARY-WING AIRCRAFT
Above: The Fa 330 was not a true helicopter but an
unpowered girokite; it was designed to be towed behind
a submarine as an observation platform.
a valuable means of instructing personnel, gliders
were to become important in themselves in a number
of roles. The first operational use of a glider to transport
troops and equipment directly into combat
occurred on 10 May 1940, when Luftwaffe paratroops
siezed and held the Belgian frontier fortress of
Eben-Emael after landing on it in DPS 230 gliders.
This was to be the most effective type in German service
during World War II, but it could be employed
only where there was a suitable, fairly large, landing
site. Focke Achgelis suggested improving on this by
substituting a three-bladed rotor unit from an Fa 223
for the wings of a DFS 230, producing what was in
effect an externally powered autogiro or giroglider,
which, when cast loose, would simply autorotate to
the ground at a very steep angle of approach, and
would thus be able to land in an area not much larger
than itself. It was to be towed behind the Luftwaffe's
maid-of-all-work, the Ju 52, and in tests carried out
during 1943, it was found to be practicable to land it
and come to a halt within 18.3m (60ft). Though the
Fa 225, as the hybrid glider was known, worked well
enough, by the time it was ready to go into production,
the Wehrmacht's operational requirements had
changed and the project was shelved.
^R
THE Fa 330'BACHSTELZE'
The Fa 225 was not the only unpowered rotary-wing
aircraft Focke Achgelis was to design. Early in 1942,
the company was asked to devise a simple single-seat
girokite to be towed behind a submarine, from which
an observer would be able to monitor a much wider
area than would a look-out stationed on the boat
itself. The result, the Fa 330 'Bachstelze' ('Water
Wagtail'), was simple in the extreme: two steel tubes,
the shorter, which supported the rotor assembly,
being set at right-angles to the longer, which held the
simple rudder assembly and the pilot's seat and rudimentary
controls, by means of which he could tilt the
rotor head (which gave longitudinal and lateral control)
and turn the rudder to change direction. The
pitch of the rotor blades could be adjusted, but not in
flight. Coarse pitch gave the best flying performance,
but made launching rather more difficult. The Fa 330
was launched by setting the rotor turning (by hand if
there was a wind; by means of a rope wound around
a drum in the rotor head if there was not) and then
pushing the whole machine backwards. Recovery
was by means of a winch under normal circumstances,
but in an emergency, the pilot could release
the rotor, which deployed a parachute from its
stowage behind the pilot's seat as it flew off. The
winch held 150m (492ft) of towing cable, which permitted
the kite to fly at an altitude of 120m (395ft);
from there, the horizon was 4()km (25 miles) away, a
marked improvement over the 8km (5 miles) horizon
from the boat itself. Without its pilot, the girokite
weighed 82kg (1801b), and could be assembled and
dismantled in a matter of minutes. Minimum speed
required to stay aloft was 27km/h (17mph).
Something like 200 Fa 330s were produced by
Weser-Flugzeugbau and were deployed aboard Type
IX ocean-going U-boats, but little is known about
their operational history beyond the fact that two or
three crewmembers from each boat were taught how
to fly them in the wind tunnel at Chalais-Meudon
near Paris. They were said to be very easy indeed to
operate, and would fly quite happily hands-off for
short periods, but were unpopular with their pilots for
reasons of self-preservation.
AMBITIOUS FOCKE DESIGNS
Focke Achgelis also produced two very much more
ambitious designs, one of them, the Fa 269, for a convertiplane,
which would have landed and taken off
vertically but then turned the shaft carrying the rotors