Convoy fights U-Boat Wolfpack

6th May 1943: Close encounter with three U-Boats - the perspective of a U-Boat hunter as Convoy ONS 5 fights back against Wolfpack Fink

The destroyer HMS Oribi, which rammed one of the U-Boats. At 03:00 on 6 May 1943 U-125 was located by radar in thick fog, rammed by HMS Oribi and disabled, she was unable to dive. At 03:54 the U-boat was sighted by the Flower-class corvettes Snowflake and Sunflower, and as Snowflake manoeuvred to attack, closing to 100 yards, the crew of U-125, realising their indefensible position, scuttled the boat. The captain of Snowflake signalled the Senior Officer Escort, Lieutenant Commander Robert Sherwood, proposing to pick them up, and received the response: "Not approved to pick up survivors."

In the middle of the Atlantic, a battle was raging. Convoy ONS5 had left Liverpool bound for Halifax on the 21st April. The forty-two ships and seven escorts soon ran into heavy weather, slowing the whole convoy down. Then on the 26th, the Kriegsmarine changed their cyphers - the Enigma decrypters in Britain were unable to break into it until the 5th May.

U-650 sighted the convoy on the 28th, and within hours many more U-boats were converging on the convoy. In total, forty-three U-Boats from Wolfpacks Star and Fink would join the operation. Among those making kills was U-264 commanded by Hartwig Looks.

HMS Snowflake, a ‘flower class’ corvette, the small ships that played such an important role in hunting the U-boats.

HMS Sunflower had just singlehandedly sunk U-638 - with no survivors from a crew of 44 - by depth charges on the 5th May.

Some idea of what that meant for the ships involved can be gained from the log of HMS Snowflake, which opened the battle with a depth charge attack on an Asdic contact on the evening of the 28th April. She was almost continuously in action from then on. In the early hours of 6th May she recorded her 10th separate attack on a U-boat.

There was a tension between making an attack on a U-boat and staying with the convoy to provide protection.

In such circumstances, the delay caused by stopping to pick up survivors from a U-boat would not always be approved:

INCIDENT SNOW 10 : 6th May 1943.
0022 Obtained R.D.F. contact bearing 090 degrees 4000 yds. Altered course towards and commenced chase illuminating target with starshell alternatively firing H.E. Reported to TAY, U-boat 3 o'clock 5 miles.
0030 U-boat dived on course 090 degrees range 600 yds.
0031 Fired heavy charges from port and starboard throwers set to 140 ft.
0032 Regained contact astern. Opened range to 1000 yds. Turned for second run in to ascertain whether U-boat had gone deep.
0035 Passed over U-boat, contact being held to "instantaneous echoes".