Fittings and Machinery

WindlassWindlass Most of the fittings that were originally located on the upper deck of the U-boat are in place. The patent anchor is secured in the hawsehole in a recess on the side of the damaged bow section.
 
Using the ISS camera, it was possible to obtain some measurements: the anchor shaft is 13cm wide. The anchor fluke measures 24cm x 20cm. The electrical anchor windlass and capstan is in place just aft of the anchor. The opening for the windlass drive shaft can be seen in the collision bulkhead above the two torpedo tubes.
 
AnchorAnchor There are a number of compressed air cylinders on top of the pressure hull along the length of the upper deck. These formed part of the boat’s compressed air system which was used to blow air into the dive and ballast tanks. All the cylinders were connected to a compressor in the control room and could be centrally recharged when the U-boat was on the surface. The individual air cylinders are 46cm wide.
 
The U-boat was armed with two upper deck guns forward and aft of the conning tower. The forward gun is still attached to its mounting and is trained upward. It is well preserved with only a small amount of fishing gear snagged around the barrel.
 
Due to low visibility and strong currents, it proved difficult to obtain accurate measurements with the ISS camera. However it appears that the calibre of the gun is larger than 10cm. The gun is fitted with a horizontally sliding breech block and top-mounted recoil cylinders.
 
Forward GunForward Gun A comparison with small calibre naval guns in use during the First World War shows that it might be a German 10.5cm/45 (4.1") Ubts L/45. This gun was in service from 1907. It was used to arm cruisers, but later in the war it was also fitted on destroyers and submarines. A 10.5cm Ubts L/45 gun from U-98 is preserved in the Imperial War Museum, London.
 
Aft GunAft Gun The aft gun is also attached to its mounting but has fallen over to the port side. This gun appears to be the standard World War One U-boat gun, the 8.8 cm/30 (3.46") Ubts L/30. This gun is attached to a circular mounting rather than the collapsible mounting used on some U-boats. The 8.8cm L/30 Schnelladekanone was originally developed for river and coastal gunboats by Krupp in 1898. During the First World War it became standard U-boat armament. An 8.8cm L/30 gun from the wreck of UB-61 is on display in the Bavarian Army Museum in Ingolstadt.
 
Conning TowerConning Tower On the conning tower, the mountings for three periscopes are visible. The two main periscope mountings are situated on top of the conning tower, forward of the escape hatch. Both periscopes were operated from the conning tower. The mountings seem to be empty and the periscopes could not be seen. The mounting for the emergency periscope is situated just forward of the conning tower. The emergency periscope was operated from the control room.
 
VentilationVentilation The column for the bridge steering wheel is situated forward of the two main periscopes. The main steering controls were located in the conning tower, but additional steering wheels were situated on the bridge, in the control room and aft in the torpedo room.
 
 The U-boat’s ventilation system has collapsed onto the upper deck and is lying across the hull aft of the conning tower. At the stern the two propellers are still attached to the shafts. The port propeller is missing one of its blades. An intact blade could be measured with the scaling camera. The blade is 75cm long and 40cm wide.