Gatwick early 1980s on a balmy summer night, whilst working nights at BCAL.
0100 ish. APU of Dan-Air BAC 1-11 starts. A few minutes later the distinctive sound of a Plessy CSDS starting engine 2 shortly followed by engine 1.
Aircraft takes off on 26 and turns left for Seaford. Massive amount of noise wakes up half of West Sussex. After about 5 minutes calm descends again.
0200 ish. Same story again, but Laker this time.
0300 ish. Same...............................
I think the one remaining airworthy 1-11 in the UK should be retained to remind people how noisy things used to be!