The winch op/winch man role could be learned by any individual who is prepared to accept what the role involves. No one is a natural fit although I would imagine the majority of RAF SAR rear crew came from the RAF loadie role and that would prove a great advantage. However, this experience will be gained given time. Cabin management is not a science in itself, underslinging doesn’t require a crewman, neither does landing the aircraft, they are both abilities that the majority of pilots acquire with experience.