XR 518 did indeed come to us from Germany when we formed "D" flight of 72 Sqn at Manston in September 74. We also had the dreaded XR 501 which had an engine failure at least once a month and XT 602, I think it was, that always limped around the sky until someone discovered that one the big metal bolts holding the main gearbox on was broken!
Pictures by 103sqn - Photobucket
