Tonytales,
Not just back then. Back in the 1980s when contra-rotating unducted fans were seen as the next big thing there was much interest in the Bear engines and gearbox; so much so that RR persuaded the MOD that they could learn a lot by recording the sound of the engines from astern in flight.
Sparing no expense on such a high-tech endeavour, one of the LU QRA F-4s was fitted hooks on the inside of the canopy frames and the pilot and navigator each issued with portable tape recorders and microphones. The next time they were scrambled for a Bear intercept they duly hung the mikes on the hooks, started their recorders and then sat in the engine wake for the next 60 minutes recording.
No permanent damage to their hearing - I think......