Air Pacific used Ded(for deduced) Reckoning and a Doppler Driftsight, which gave drift in real time on their BAC 111 's for years on their longer (for a BAC 111)legs. Know the track required, know the actual drift, apply it accurately, read the groundspeed, and you end up where you should. With a full load of pax (albeit not many by todays numbers) they didn't have much fuel left over to muck around on arrival either sometimes. They had to turn back now and then to top up with fuel if they ran into unforecast headwinds. And if there was a thunderstorm hailing cricket ball sized ice sitting over Brisbane on arrival, the divert to Rocky required attention as observed from the only seat left, the jumpseat, on one occasion. First into Rocky and first out again, just as the diverted Melbourne and Sydney 72's were arriving. That was the technology of the time.