German aircraft inferiority: Interesting. I\'ve always found the low quoted top speeds of the Fokker D.7 anomalous, given its reputation. Period cross-sections in Flight magazine etc show German aerofoils had much more camber than British aerofoils, thus more high-lift in their characteristics, but also more drag. The unbraced D.7\'s aerofoil is thicker as well (compared with earlier braced types like the Albatros). It\'s also a large aeroplane - I was struck by its height, depth, & general bulkiness when I examined the example in the Deutsches Museum in Munich. By comparison, an SE or SPAD is a very small aeroplane. As the articles says, the Hispano was also a higher technology engine, more horsepower per cc and per pound. I suppose factors like these explain why the D.7 was not as fast as its reputation suggests.
Why then the reputation? The business about it \'hanging on its prop\' is puzzling - it\'d stall out like any other aeroplane; it can\'t defy the laws of physics. However pilots\' reviews of surviving flying examples emhasise its impeccable handling, which prompts a hypothesis: the D.7\'s thicker, more cambered aerofoil provided better behaviour close to the stall, & a lower stalling speed. Thus the SE stalls out in a zoom quicker than a D.7, and its departure from controlled flight is moreover more dramatic, with sudden pitch-down & wing drop. Meanwhile the D.7 is still flying (sort of) & mushes gently down as it stalls with the nose still high. Thus the impression of hanging on its prop. Some aircraft are like that - they maintain nose attitude but they\'re stalled - just look at the altimeter winding down!
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Why then the reputation? The business about it \'hanging on its prop\' is puzzling - it\'d stall out like any other aeroplane; it can\'t defy the laws of physics. However pilots\' reviews of surviving flying examples emhasise its impeccable handling, which prompts a hypothesis: the D.7\'s thicker, more cambered aerofoil provided better behaviour close to the stall, & a lower stalling speed. Thus the SE stalls out in a zoom quicker than a D.7, and its departure from controlled flight is moreover more dramatic, with sudden pitch-down & wing drop. Meanwhile the D.7 is still flying (sort of) & mushes gently down as it stalls with the nose still high. Thus the impression of hanging on its prop. Some aircraft are like that - they maintain nose attitude but they\'re stalled - just look at the altimeter winding down!