RAF Exchange Tour with the RAAF
In the mid/late 60s two RAF pilots and an RAF navigator who were serving on an exchange tour with an RAAF transport squadron were asked, after they had completed their first 6 months flying within Australia and could now be cleared to operate beyond its shores, if they wished to take part in the schedules that supported the RAR detachments in South Vietnam - as were their Australian colleagues. Of course the answer was 'Yes'.
All sorties leaving their Australian Base had to be authorised, but the RAF aircrew's names were entered in pencil* and they were accompanied by a lesser qualified Australian pilot/navigator who was the 'official' crew member. Initially, the aircraft routed to/from Butterworth via Pearce and the Cocos Islands (due to Confrontation with Indonesia) and later via Darwin and Singapore.
Sorties were flown from Butterworth principally to and between Vung Tau and the Saigon airfields in '66 and '67, bringing in personnel and stores (especially fresh Australian milk), and collecting those who were going home. The aircraft didn't remain in Vietnam overnight but flew up to Ubon as this was a safe haven.
Of course, the RAF Support Unit at Edinburgh had to be informed that these sorties were being flown, and they in time reported this back to the UK. This resulted in the RAF aircrew being told not to continue to join their RAAF colleagues in supporting the nation's participation in the ANZUS expedition. This was followed by Canberra demanding an early end to the RAF exchange with this squadron.
However, ties forged with the Aussies 50 years ago were strong enough to endure, and I know of one who will be marching in Sydney this year on ANZAC Day, proud to be amongst his former colleagues once again.
* 'In pencil' so that if the worst happened the squadron could erase the entry and deny that participation had been authorised!! However, as one RAAF pilot put it, "If do we have to force land in South Vietnam, the first thing we do is shoot the Poms!"