Rabaul was indeed one of the definite highlights for anyone who was there back in the day. Flew into there regularly from Hoskins with Talair and was based there for 6 months with PX, late 70's to mid 80's. The diving, the yachtie, the flying, the mangoes, all in a haze of SP, too many good memories to list. Flying highlight was always trying to do circuit inside the caldera wall for rwy 32 in an F28...
Saw some great photos years ago of some of the aircraft caught in the Matupit ash after the volcano.