Spit IIa

[Crumpp]

Spitfire was a bad aircraft,

Who said the Spitfire was a bad aircraft? DC-3 is not a bad aircraft either.

the marginal mkV

The RAE investigated a series of fatal accidents and concluded that pilots were overloading the airframe on recovery.

The longitudinal instability was not corrected until the Mk V with the installation of bob weights to increase the stick force per G. Bob weights certainly help the pilot to maintain better control of his accelerations but they did not fix the actual problem of insufficient vertical and horizontal stabilizer area. That too was fixed in later marques as stability and control matured greatly as a science during the war. At the time the Spitfire was designed, the United Kingdom did not have a standard and there was no such thing as a stability and control engineer. It just was not that big a deal at the low speeds of open cockpit biplanes common before the war. As speeds and power increased though, it became very important.

Nothing that Crumpp has says is a non-sense unless over interpreted by the reader. It fit actually many well known aero principles.

Yeah folks are very emotionally tied to the Spitfire. I can even remember students in class defending it. That is why it makes such a good example for fledgling stability and control engineers.

Think about what the NACA says on the stick travel. You only have 3/4 of an inch of travel to run the wing from a CL of .3 to CLmax. The minimum standard was 4 inches.

It is no wonder the Operating Notes suggest the pilot brace himself on the cockpit walls to control the aircraft. Imagine trying to land on a gusty day getting tossed around the cockpit with only 3/4 of an inch movement between controlled flight and a stall spin accident.