@Keg, I am not a pilot type but the first time I heard the rumour was in '93 (I specifically remember the years due to the reason I was at the party chasing a specific bit of tail) from a Cathay skipper. Now, I know no actual working of how Qantas used them but the version I got was that it was a 767 and a Cadet Captain and there was a Training guy as a passenger who saved the day by coming and seeing if he could help when it became obvious they missed out few times.