ADM 199 1782 Proceedings of U-boat assessment committee. Attack on U boat by NIGER

 Précis of Attack by NIGER

Date:                1.4.42
Time:               1945
Position:           70° 22’ N, 36° 10’ E.
Depth of Water: 100 fathoms
Weather:          Wind light, Sea calm, Weather overcast with snow showers, Visibility 10 – 500 yards in snow. 

NARRATIVE

NIGER was carrying out a search for the whaler, SULLA, which had become detached from the Convoy PQ13. At 1945, whilst zigzagging to the Eastward, NIGER sighted three torpedoes approaching from her port quarter. Course was altered to comb the tracks and NIGER then proceeded at full speed along the tracks which could be easily seen in the flat calm sea. A very good contact was obtained at a range of 4,000 yards and 60° on the starboard bow. NIGER turned towards and carried out an attack with five depth charges set to 150, 250 and 350 feet. Unfortunately NIGER had a defective asdic dome owing to which contact was distinctly woolly when within 20° of the bow. Nevertheless contact was held down to a short range and the time to fire was obtained by recorder. Contact was regained and a second attack was made with five depth charges and using the same depth settings. Contact was lost after this attack and although a thorough search was carried out no further contact was obtained. At 0300 NIGER resumed her original search for SULLA. 

SURFACE EVIDENCE

Torpedo tracks were clearly seen on the calm sea. 

ASDIC EVIDENCE

Asdic conditions were good but NIGER found results difficult to obtain owing to her leaky dome. The contact appeared to move in both attacks and was held down to a short range. A track chart has been forwarded. 

CO’S OPINION

Both attacks were good and although there was no indication of damage there was little doubt that some must have been done. 

RAD HF’s OPINION

The setting of the depth charges is considered too deep in view of the fact that the U-boat would probably have been at periscope depth to fire the torpedoes. In view of the deep settings used and the crossing movement of the U-boat, a course to pass ahead of the U-boat should have been steered and not one that took the ship over it.

The movement of the contact between the first and second attacks, as shown on the track chart, indicates the speed of the U-boat as being approximately 20 knots. This is impossible and it is for consideration whether either the second attack was carried out on a non-sub, or whether an inaccuracy exists in the plot. The search subsequent to contact being lost does not appear to have been extended sufficiently far to the Northward in view of the fact that the U-boat’s movement had until then been in a North Easterly direction. 

SUBMARINE TRACKING ROOM’S OPINION

Tracking evidence confirms the presence of a U-boat but suggests that no damage was inflicted on it. 

DECISION OF U-BOAT ASSESSMENT COMMITTEE

Insufficient evidence of damage. 

18^th June 1942