Arse-End Charlie: the rear gunner, also known more politely as Tail-End Charlie
Crump Dump, The: the Ruhr.
Flaming onions: anti-aircraft tracer rounds.
Humdinger: a fast aircraft
Hurry: A Hawker Hurricane
Kipper kits: aircraft tasked with protecting convoys in the North Sea.
Midwaaf: a bossy NCO of the Women’s Auxiliary Air Force (from midwife).
Mouldy: a torpedo.
Screaming downhill: making a power dive.
Shagbat: a Supermarine Walrus.
Snargasher: a training aircraft (such as the North American Harvard), from tarmac-smasher.
Part 1 can be found here.