On August 19, 1942 the Allies launched operation Jubilee, more famously known as the Dieppe Raid. With over 60 squadrons tasked to take part and all the military shipping in the area rescue was considered. After deliberations within five miles of the landing beaches the Royal Navy would take care of rescue duties. Outside of that area it fell the fledgling, newly formed SARF force of the RAF. During the course of the day 47 SOS's were received and 31 rescue vessels attended. Most were High Speed Launches (HSL's), which were just wooden boats, with no armour and crammed with fuel tanks. On top they had a pair of .303 Browning's to defend themselves. Their standing orders were not to open fire unless fired upon. They were planned to operate under the air umbrella for the Dieppe operation, however often the launches had to leave the cover to make a rescue, which exposed them to enemy aircraft.
The HSL's from Dover were mostly crewed by men from 961 Squadron, which had flown barrage balloons.
Things got worse as four more FW190's pounced on 123. The launch weaved around several times to shake off the pursuing German planes, cutting a huge wake in the water at a speed of 36 knots. When the 190's broke off 123 turned to the north west and made to link up with her sister ship HSL 122.
Cpl Nunn raced for the engines where he struggled to shut them down (the source on this fails to say why he tried to shut them down). The fumes from the engines were filling the room where he was working, choking he staggered on deck nearly fainting from the fumes. He ran to the wheel and set course for England.
At about 1715 HSL 123 spotted Cpl Nunn's stricken boat with the Heinkel bombers still overhead. By the time 123 pulled alongside the stricken craft the Heinkels had left the scene. As 123 pulled alongside, she tied up to the badly damaged boat and began to transfer the wounded.
As 177 and 513 reached the area they set about picking up the crew. At this point FLt Morrison saw an unconscious body floating away from the area. Unhesitatingly he dived into the sea of burning oil and swam out to the body. It was LAC Dargue, 122's wounded medic whom had kept his colleagues alive despite his own injuries. FLt Morrison towed LAC Dargue back to 177. Having found all the survivors and with the end of the day closing, and packed full of people pulled from the sea 177 made a course for home.