Leslie Boon enlisted in the Royal Australian Air Force (RAAF) on 26 February 1943. He was posted to No 576 Squadron RAF, a Lancaster bomber unit raised in England. Leslie recalled a most memorable daylight raid carried out on Anzac Day in 1945 against the town of Berchtesgaden, situated high in the Bavarian Alps near the Austrian border. The target was the SS Barracks opposite the nearby mountain retreat of Obersalzberg, which included Adolf Hitler’s alpine lodge and other dwellings owned by senior Nazi leaders. Leslie did not know whether they hit the target or not, but he did remember the picturesque approach over the Swiss Alps, which were carpeted with snow.
The raid would be No 576 Squadron’s last for the war, but Leslie remembered undertaking several trips as part of Operation Manna, a food lift to the stricken and starving civilians of the Netherlands. He was amazed by the signs of 'Thank you’ that were laid on the ground by Netherlander civilians. It was, he said, the best thing about the mercy missions.
He discharged from the air force on 12 December 1945, having attained the rank of warrant officer.