RR Test Pilots
RR used to insist that their pilots join the aircraft development team, e.g. we had a RR tp come to Warton to do Adour development on the Jaguar. I believe they sought support from MOD to persuade BAe to agree. I could never understand the logic but they did help to progress queries and proposals raised by the home tp's. It seemed to me to be more appropriate in the civil world where they could bring RR knowledge to the manufacturer and get experience of the engine on the route by riding the jump seat.