As you probably know, the film's producer, Euan Lloyd, (he of 'Wild Geese' fame) was 'inspired' to create 'Who Dares Wins' by the events of the 1980 Iranian Embassy seige in London having resided not far from the scene of the action and having watched (as many did) the events unfold on TV. Much (if not all) of the aerial footage from the Iranian Embassy seige was filmed with a Heli-Tele fitted to an ex-Ferranti MBB Bo105 (G-BFYA) which was on contract to Metpol.
Ex-Ferranti Bo105C G-BFYA on contrat to Metpol and seen at Battersea in 1980