<< bright young third-pilots from Hamble, who would spend much of their time practising astro for their Nav Licences. >>
As one of those bright young pilots from Hamble - I am tempted to ask just what, other than astro, would one have used? I don't recall much Loran over the Eastern Sahara - NDB's were almost non-existent and those that were available were bugger all use - the wx radar would paint up Nassar's corner - but only then when we could overfly Libya - after that it was over Egypt and that was a beacon crawl using the famed NDB's and occasional VOR's
Ah the memory of circum-zenith fixes over the desert!
And by the time I crossed the Western Sahara for the first time - it was all triple IRS's