British anti-aircraft gunners firing a 94-mm cannon (Ordnance QF 3.7 inch). 
The 3.7-Inch QF AA was Britain's primary heavy anti-aircraft gun during World War II. It was used throughout the war in all theaters except the Eastern Front. 

Heavy AA gun

my liberator B24J in Italy with205 Group. We bombed marshalling yards and dropped supplies to Tito's Forces in Yugoslavia among other targets

The Battle of the Atlantic has yielded many fine stories of air attacks on underwater craft, but Flying Officer Trigg's exploit stands out as an epic of grim determination and high courage."

It was on the enemy's testimony that the award was given.

The U-boat sank, but the seven survivors were rescued by a Royal Navy vessel and the captain reported the incident, recommending Trigg be decorated for his bravery. The Victoria Cross was awarded posthumously.

He was the only Allied serviceman in either World Wars 1 or 2 to be recommended for a Victoria Cross by the enemy.

In May 1998, Trigg's V.C. was sold at auction by Spinks of London for £120,000, the equal highest price ever realised for a V.C. The seller was not believed to have been a relative of Trigg, and the buyer was anonymous.

