I have most of the Buccaneer episodes on a tape somewhere, but the flying scenes were few and far between. The backround sounds in the cockpit shots sound authentic and very much a low beat of prop blades. At which power setting their recordings were made is a mystery though.
G-BHAU was used for many flying shots, notably the final 'Emergency' episode, the camera trying to miss the reversed red fin and Redcoat titles by only focusing on the lower fuselage.
in cruise on the flight deck about all you heard was prop noise as you describe "low beat" don't know what the Brit sounded like when new and tight - by the time we got them they were 20 years old and there was alot of wind noise on the flight deck.
it wasn't an aircraft that you flew without a headset -