IX U boats - Solitary Raiders

[kiwi_2005]

Some facts taken from the book "U-boat far from home" by David Stevens about the Type IXD2 U-862 voyage around Australia/New Zealand. Most your probably already know but its a first for me about the Bachstelze

IX U boats -Solitary Raiders
Being comparatively slow to dive and hard to manoeuvre, the Type IX was
unsuitable for convoy battles, but this was never intended to be its role. It
was instead to be a solitary raider, laying mines off foreign coasts or using
its high speed and endurnace to catch the fast,
independently routed merchant ships encountered in distant waters.

Donitz suggested the need for a boat that could apply 'strategic pressure in very remote territores'.
The development of a completely new U-boat
would have entailed significant delays and further stretched the building
yards, already overloaded with wartime production. Instead, it was decided
to enlarge the existing Type IXC. This solution would offer cost advantages
and have far less impact on the overall contruction schedule. The result
was the Type IXD2 Officially designated a U-Kreuzer (U-Cruiser),
the Type IXD2 U-boats were commonly known as UberseeKuhe (Super or oversea cows)
Twenty nine of this type were eventually commissioned.

The Bachstelze
IXD2 - came with the FockeAchgelis FA-330, more commonly known as
the Bachstelze (Water-wagtail). The Bachstelze was an unpowered,
single-seat autogyro. The Pilot sat on metal frame against an aluminium
mast on top of which were three cloth-covered blades, each about 3m long.
Before being launched, the machine first needed to be assembled on a small
platform abaft the storage containers. When ready the U-boat would head into
the wind until the relative velocity was suffient to turn the rotor
blades at between 130-360rpm. As the Bachstelze rose, a towing cable
would be pulled slowly from a third container beneath the launch platform.
Thus tethered, this precursor of the helicopter effectively gave the U-boat
a 100-150m viewing platform. The pilot was provided with a parachute
and passed messages to the tower on a telephone. Though it had potential
to extend the U-boats's from diving quickly and hence could only be used
in remote areas, where allied air patrols were unlikely.

The FuMB 26 Tunis was fixed on top of a wooden rod and attached to the
periscope standands or into the D/F loop. The Tunis provided
counterdetection at ranges between 50km-70km, but the aerial was not
watertight and had to be dismounted before diving. (Does SH3 have the FuMB 26 for the IXD2?)

It should be kept in mind that even after modification there was nothing
revolutionary about the Type IX U-boats. Developments between the wars
had provided improvments in fire control, torpedoes, communications,
diving depth and shock resistance, but the basic design remained
conventional. In most areas the Type IX was only slightly superior to
Germany's large ocean going U-boats of the previous war. Thus the boats
that Germany had in service in September 1939 were submersibles rather
than true submarines and could not complete with the rapid advances in
anti-submarine techniques that occurred during the course of the conflict.
By August 1943, with U-boats forced to spend longer and longer periods
submerged, all the pre-war types were recognised as obsolescent.