"I have HUD video showing 51,220 feet".
FRS1 altitude spec was increased in late 80s. Caused all sorts of problems, particularly with radar power supply encapsulation which failed at about 45k, but well above orignal spec. Fix found and testing programme planned. MoD Beancounter - "How do you plan to test it at 50,000ft if you need two test engineers, test equipment and, presumably, a pilot?" Ferranti Chief Test Engineer - "Using a f****** long cable".