Other ships in the group (the corvettes), could not catch a U-boat on the surface, but by 16 May, the convoy had moved out of the danger area. In April 1944, Macintyre left "Hesperus" (very reluctantly), to assume command of , an American-built ship. He would also take charge of the 5th Escort Group, then forming in Belfast. After a working-up period, the group began operations on 21 April, supporting the escort of convoy ONS 233. Having found themselves under-used, the group was re-deployed, carrying out an abortive sweep for a single U-boat before joining the escort aircraft carrier "Vindex" and the 9th Escort Group on the 26th. In the early morning of 5 May, following a lengthy hunt, the half-group (the other half were kept with "Vindex"), were sent to an area known to contain a U-boat which was on weather-reporting duty. With the use of direction-finding equipment and aircraft from "Vindex", the search area was reduced. Having found his target, Macintyre then decided to use the 'creeping' attack method pioneered by Captain 'Johnnie' Walker. This involved the use of a second ship, (in this case the frigate HMS "Bligh"), to do the actual attacking while the first ship ("Bickerton"), controlled things such as the ASDIC tracking. A series of depth charge explosions were rewarded with the sight of a badly damaged U-boat breaking the surface. "Bickerton" moved in to administer the "coup-de-grace", but she was beaten to it by a Swordfish from "Videx" which dropped two more depth charges on the hapless German vessel. A handful of survivors were taken prisoner. Upon questioning the prisoners, it was realised that "U-765" was to have been relieved, (by, it was later discovered, "U-736"). It was decided to repeat the attack, but it was unsuccessful. Before and after D-Day (6 June 1944), Macintyre, "Bickerton" and the 5th Escort Group were part of the RN's contribution to the invasion of France by patrolling in the relatively shallow waters of the Western Approaches. On the 15th, the group were investigating the sighting of a U-boat using its snorkel. HMS "Mourne", a ship well known to Mcintyre, was the victim of an acoustic torpedo.