Sergeants Leo Francis O'Hara and J.F. McQueen were posted to 419 squadron after completion training at No. 82 OTU at RAF Ossington followed by heavy conversion training at No. 1659 CU at Topcliffe on August 10th 1944.
The other crew members were:
Pilot P/O Aston Irving Cohen (KIA October 9th, 1944)
Navigator F/O Gerald William Murphy (KIA October 9th, 1944)
Bomb Aimer P/O John H. E. Goldfinch (KIA October 9th, 1944)
WAG Sgt. Robert Francis Emerson (KIA October 9th, 1944)
F/E P/O Russell A. Campbell (KIA October 9th, 1944)

Combat Report August 29/30 1944

The night of August 29/30 found the crew on a bombing run on Stettin when Sgt. McQueen spotted an ME109 on the port quarter up at about 500 yards off. He gave the corkscrew to port order, as the enemy came in closer for the attack Cohen decided to release the bombs before going into the corkscrew. By 350 yards the Me109 was opening fire, both McQueen and Sgt. O'Hara opened up with long bursts of 200 rounds each. The enemy fighter broke away to the starboard side heading below the bomber. The resume course order was given.
The Me109 or another one next appeared up on their starboard quarter above them, this time it was spotted by O'Hara who them gave corkscrew to starboard order. The fighter gained on them and both Sgt. McQueen and Sgt. O'Hara opened fire on him at about 300 yards. The fighter broke away from his attack to the port side without firing at the Lancaster. In total the two gunners had fired off 400 rounds each in defence of their crew.

McQueen's Escape from KB754

On a raid to Bochum, F/S O'Hara along with the rest of P/O Cohen's crew were killed when KB754 exploded after being attacked. Sgt. McQueen was thrown from the rear turret by the blast. He was partly trapped in the turret by the effects of the blast, his right leg was caught in the framework of the rear turret. The Lancaster was diving nose down and on flames, as the fire reached his clothing and started to scorch his clothes he pulled his parachute cord. The force of the drag from the chute pulled him from the entrapment. Sgt. McQueen became a PoW at Stalag Luft VII.