a twin engined freighter, (Argosy) and also on 17th July 1983 an Aero Commander 685 Whisky Juliet Charlie
Was a Bristol Freighter rather than four engine Argosy, the Aero Commander event the chap could highly likely been rescued had their not been a balls up in organisation.
The various other helicopters available can be discounted as first priority rescue craft on the grounds of unsuitable location, being single-engine, or not being winch-equipped. The possible exception was one of the Bell 205s at Longford. These, although single-engine,are equipped with floats and a suitable winch, and being on SAR standby for the oil drilling platforms, had a better response time than either the S76 or one of the B212s.The situation at Longford on 17 July was unusual. Regular helicopter flights had been cancelled because of an industrial problem on the oil rigs, with the result that the S76, B212 and B205 helicopters were all on the ground, with one standby crew and maintenance personnel immediately available. The B205 was ready to go and the operator estimated that the S76 or B212 would have required 20 minutes to fit a winch.The SARMC did not check the availability of the helicopters at Longford. He reported later that this decision was based on his view that the response time would have been too long, from his personal knowledge of the organisation gained in previous visits and discussions.
The response time of the 205 and S-76 were similar, although the 205 had a winch permanently fitted it still required refuelling, seating removed, stretcher, slings etc loaded. The S-76 likewise, with the addition fitting the winch which was a quick job. Cruise speed of the S-76 would have put it on task quicker than the 205, 155 versus 100 knots cruise, the Vne in both cases. We only found out about the ditching on the TV news that night, no body contacted us. Was working that day, there would have been at least four other crews also, caused us a fair measure on angst.
https://www.atsb.gov.au/media/5226548/198302284.pdf