I underwent conversion to the first HS 748 destined for the RAAF VIP Squadron based at Canberra. That was late 1966 and we did our four hour conversion (flying) course on G-ARAY at Woodford in Cheshire. There were no nicknames for the aircraft at the time. The chief test pilot at the time was Jimmy Harrison and with him was Tony Blackman, Bill Else and Eric Franklin.
Jimmy Harrison displayed the first 748 in India where it was to be built under licence. G-ARAY was not equipped with weather radar in those days. Jimmy inadvertently penetrated a severe thunderstorm and frightened himself considerably when the aircraft was caught in a massive updraft with its associated violent turbulence.
I recall Jimmy telling us (RAAF pilots) that he kept muttering to himself as the 748 went up and down in the cloud "this aircraft is built fail-safe, this aircraft is built fail-safe etc etc" because that was one of the main selling points of the 748 design. On return to Woodford after that fright, Jimmy ensured radar was fitted to all future 748's.