autogyro wrote:
All post war supersonic flight owed much to German aviation developments during WW2.
The B1 flown by Chuck Yeager would not have been successful breaking the sound barrier if it had not used the fully flying tailplane developed by Miles aviation in the UK, or if it had not used the huge amount of German technology captured at the end of the war.
Piston engined aircraft would only reach Mach 1 in dives beyond full control and the usual result was reversed control surface response and a crash.
The Hunter was 'transonic'. It used the British designed and developed turbo jet engine, the details of which were strangely given free of charge to both America and Russia.
IMO the UK had a bit more knowlege than others, hence the (RAE Farnborough) 'slab' tailplane as above
(the 8th USAAF lost many P47s and P38s in dives, RAE fixed the P47 for them, the P51/Merlin came about from this)
non-supersonic aircraft have normal (ie undercambered/asymmetrical) wing sections for efficiency
(giving sudden CoP movement beyond some 'critical' Mach no, ie a huge and sudden change in (pitch) trim)
this trim change (usually nose-down) cannot be contained by pilot use of the elevators or trimmer (but he will try)
the apparent 'death dive' tends to naturally recover near the ground as warmer air reduces the Mach no below Mcrit
the pilot is applying a nose-up trim/control etc without result, as the plane drops below critical Mach no there is sudden nose-up 'g'
the pilot then choses a nose-down input, hence there is a (mistaken) impression that there is/has been control reversal
eg all airliners have this characteristic, and such dives and recoveries can still occur today
(autopilots trip out when in difficulty and ring an overspeed warning to prevent the above, but it still happens)
recoveries can cause tip stalling, where the CoP moves forward, producing 'pitch-up' and sudden nose-down commands by the pilot
'the control reversal concept was used (in the UK) to define roll control
(aileron action twists the wing, partly opposing the aileron's effect, beyond a certain 'control reversal' speed the wing twist dominates the aileron and the resulting roll is opposite to that commanded)
eg stiffer Spitfire wings had a nominated reversal speed of 820 mph, so at speeds used they had enough roll control
the USA paid (about £6 mill ?) for a general right over turbojets, then paid fees for the 20000+ UK designed engines they built
(this saved Pratt & Whitney (J42 & J48) and Curtiss-Wright (J67), the UK had little use for its engines),France etc paid fees
the UK position would have been stronger (regarding priority) if Whittle had avoided the handicap of reverse-flow combustion
(which route was taken to save critical time by using parts made for his earlier design involving heat exchange ?)
(thereby no Whittle engine was useful for service, the UK position was transformed by Halford (DH), Hooker (RR) and MetroVick)
the USA funded the whole engine development that led to the Harrier (+50% for the airframe) via Mutual Weapons Development Fund
the US Marine Corps saved the Harrier (and it saved them from the US Navy, similarly the USMC liked UK hovercraft)
the Hunters exported to Europe were 100% funded by the USA
(they such poor servicability that they were bought back by Hawker almost unused and sold-on elsewhere, says Roy Braybrook)
BTW ..... didn't that Art Arfons (some time ago) do a good job !
