Rvusa
This must have been a specially modified F6 as the F6 never carried 230gal drop tanks in service - the inboard hardpoints weren't cleared for them . It was only when modified to F6A which included strengthening the hardpoints that 230gal drop tanks were cleared for the inboard pylons. I also suspect that this particular F6 was stripped down and that it din't land at El Adem with much in the way of reserves. Certainly my experience and that of other posters above is that 2¾ hours was about as far as as in-service a/c could go landing with a degree of diversion fuel. or 3hrs without
KenP
Your Gib-West Raynham sounds a bit like my Gib-Brawdy. TAFs were fine at launch for our en-route div of Porto and wx div of St Mawgan but both went out in sea fog however Brawdy was OK (just!) so we pressed on. St Athan was now the only div (no Chivenor in those days) and we hadn't enough fuel to land with that so Brawdy held all recoveries until we were down.
Your 3hrs must have been very tight indeed.
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