"would lift a tank as well as a fuelled airframe "
to be fair the illustration shows Saladin Armoured Cars - about 11 tons a piece
And it was originally to be STOL not VTOL, with a payload of 35,000 lb
Still mad but stranger things have flown,,, and been bought - tho why the OR branch kept insisting on UK-Ascension range is beyond me
If there hadn't been a knock down fight over the engines that wasted a couple of years it might well still have been in service