Folios 235-253: CB number 01437 O.X.O, Copy number 439, UB.55 Interrogation of Survivors,...

Folios 235-253: CB number 01437 O.X.O, Copy number 439, UB.55 Interrogation of Survivors, May 1918. UB. 55 was sunk on 22 April 1918.

Folio 236: Cover sheet, UB.55.

Folio 237: Table of Contents.

Folios 238-239: Last Cruise of UB.55 (sunk on 22 April 1918). UB.55 left Zeebrugge on 21 April 1918 for the English Channel. After submerging a loud explosion was heard, probably from a mine. Water entered the stern compartment and engine room. The submarine could not surface and settled on the bottom in 25-30m. Water entered the control compartment and the batteries began to gas. After a number of attempts, the Captain and Engineer escaped from the conning-tower hatch and about 20 from the foremost hatch. Of those who made it to the surface only six were rescued by a passing trawler.

Folio 239: Remarks on the Survivors of UB.55. The captain, Lieutenant-Commander Ralph Wenninger had previously commanded UC.17. The engineer, Sub-Lieutenant Friedrich Dietrich was also an experienced submariner.

Folio 239: Previous Cruises of UB.55: (1) October 1917 Returned early with defective ballast tanks. (2) October 1917 English Channel, one steamer torpedoed Bay of Biscay, a steamer and trawlers sunk. (3) Bay of Biscay, steamers and fishing vessels sunk and then rammed and badly damaged UC17. (4) Bay of Biscay, a number of ships sunk.

Folios 239-245: General Details of UB.55: General Description, Accommodation, Air Purifying Apparatus, Air Service, Batteries, Bilge Keel, Bulkheads, Clutches, Compasses, Air Injection Compressors, Conning-tower, Depth-Gauges, Depth when Submerged, Diving Capabilities, Engines, Exhaust, Fresh Water Supply, Fuel, Hatches, Hydroplanes, Internal Arrangements, Jumping Wires, Kingstons (Flooding Flaps), Lubricating Oil, Motors, Navigation Apparatus, Periscopes, Salvage Arrangements, Silent Running, Sound Signalling Apparatus, Steering Gear, Tanks, Telephone Buoys, Thrust Blocks, Trimming Pump, Turbo-blower, Venting Arrangements, Wireless Deck Tube, Wireless Mast. Plate 1: Lohmann Clutch (folio 241). Plate 2: UB.55 (folio 245). Plan of Compartments and External Tanks. Plan of Venting Arrangements, Domes and L.P. Blows of External Tanks.

Folio 246: Flanders Submarine Flotilla: Command structure of the Flanders Flotilla. Submarines: UB.10, UB.12, UB.16, UB.17, UB.30, UB.31, 3 UB.3, UB.40, UB.57, UB.59, UB.74, UB.78, UB.80, UB.103, UB.106, UB.108, UB.117, UC.4, UC.17, UC.56, UC.64, UC.70, UC.71, UC.75, UC.77, UC.78 and UC.79.

Folio 247: Submarines Lost: UB.38, UB.54, UB.56, UB.58, UC.6, UC.10, UC.18, UC.21, UC.36, UC.39, UC.47, UC.48, UC.50, UC.51, UC.61, UC.62, UC.65, UC.69, UC.72 and UC.75.

Folios 247-248: Torpedoes: Reliability of lever pistol and of intricate magnetic pistol. Plate 3: Torpedo Lever Pistol (folio 248).

Folio 248: Explosive Charges hung underwater on the outside of a vessel. Plate 5: (a) Explosive Charge, (b) Arrangement for Raising W/T Masts (folio 252).

Folio 248: Anti-Submarine Measures. British mines and depth charges becoming more effective and destroyers are more active. Dazzle Paining is not effective.

Folio 248: General Remarks. Submarine losses due more to inexperience of crews. Submarines will not be a decisive factor for victory but will prevent America sending a large number of troops.

Folios 249-253: Appendix I: Tank Capacity (folio 249). Plate 4: UB.55 Air Service (folio 250).

Folios 250-251: Appendix II: Key to Diagrammatic Sketch of Air Service.

Folio 252: Appendix III: list of crew, UB 55 (folio 251). Names and ranks of crew identifying prisoners and those lost.

Folio 253: Plate 6: UB.55, General Arrangement drawing of internal profile and deck plan.