ONS 5 was the 5th of the numbered ONS series of Slow trade convoys Outbound from the British Isles to North America. The North Atlantic battle surrounding it in May 1943 is regarded as the turning point of the Battle of the Atlantic in World War II.
ONS 5 consisted of 43 ships bound from Liverpool to Halifax. The ships were either in ballast or carrying trade and export goods.[1] The convoy departed Liverpool on 21 April 1943, and would arrive in Halifax three weeks later on 12 May. It was under the command of JK Brook RNR as Convoy Commodore, traveling in the Norwegian freighter Rena.[2] The escort was provided by Mid-Ocean Escort Force group B7, 7 warships under Captain Peter Gretton, in the destroyer Duncan. Also in the group were the destroyer Vidette, frigate Tay, and corvettes Sunflower, Snowflake, Loosestrife, and Pink. The group also contained 2 trawlers, Northern Gem and Northern Spray as rescue ships, and the fleet oiler British Lady for mid-ocean re-fuelling. The convoy was joined by other escort vessels as the battle progressed.
In the course of a week, ONS 5 had been the subject of attacks by a force of over 40 U-boats. With the loss of 13 ships totalling 63,000 tons, the escorts had inflicted the loss of 6 U-boats, and serious damage on 7 more.
This battle demonstrated that the convoy escorts had mastered the art of convoy protection; the weapons and expertise at their disposal meant that henceforth they would be able not only to protect their charges and repel attack, but also to inflict significant losses on the attacker.
ONS 5 consisted of 43 ships bound from Liverpool to Halifax. The ships were either in ballast or carrying trade and export goods.[1] The convoy departed Liverpool on 21 April 1943, and would arrive in Halifax three weeks later on 12 May. It was under the command of JK Brook RNR as Convoy Commodore, traveling in the Norwegian freighter Rena.[2] The escort was provided by Mid-Ocean Escort Force group B7, 7 warships under Captain Peter Gretton, in the destroyer Duncan. Also in the group were the destroyer Vidette, frigate Tay, and corvettes Sunflower, Snowflake, Loosestrife, and Pink. The group also contained 2 trawlers, Northern Gem and Northern Spray as rescue ships, and the fleet oiler British Lady for mid-ocean re-fuelling. The convoy was joined by other escort vessels as the battle progressed.
In the course of a week, ONS 5 had been the subject of attacks by a force of over 40 U-boats. With the loss of 13 ships totalling 63,000 tons, the escorts had inflicted the loss of 6 U-boats, and serious damage on 7 more.
This battle demonstrated that the convoy escorts had mastered the art of convoy protection; the weapons and expertise at their disposal meant that henceforth they would be able not only to protect their charges and repel attack, but also to inflict significant losses on the attacker.
