Stability and Control characteristics of the Early Mark Spitfires

[NZtyphoon]

Originally Posted by MiG-3U

Hm... so it was the X4268 which went to Farnborough for aileron testing Aug 40, the tests for wing failures were July 41.

Interesting interpretation

This is clearer http://www.spitfires.ukf.net/p014.htm

X4268 Ia 1066 EA MIII FF 24-8-40 AMDP VA 24-8-40 RAE 9-40 aileron trials pilot J Quill. RAE 7-41 flight measurements of wing internal pressure for invest into struct fail of Spit wings. returned VAWD for continuation of trials.
ASTH for flaps mods. CRD AAEE 8-9-41 M45 install. Strengthened flaps tested as air brakes. 18-10-41 trials with thermostatically operated rad shutter ros VA 18-10-41 CRD DeH 23-11-41 39MU 18-2-42 3SGR 10-3-42 CF PRU engine failed wheels up landing nr Weeton Lancs CE 21-4-42 SOC 30-4-42

Opinions of an aerodynamicist:




No mention of longitudinal instability being a problem...
and an accident inspector:





(X4421 Ia 1138 EA MIII FF 12-9-40 8MU 13-9-40 66S 16-9-40 57OTU 21-10-40 steep dive from low cloud violent pull out high speed stall spun wing fail Pilot thrown clear but killed 15.15hrs crashed Northrop Flints 27-3-41 SOC cancel RAE 8-4-41 AST 13-5-41 rebuilt as Va M45 164S 29-4-42 FACE 18-8-42 (Rebuild suspect) )

One of the major causes - aileron instability caused by stretching cable - again no mention of longitudinal instability.