While no one can argue that the NACA was not at the forefront of aeronautics in the mid 1930's, the bashing of British aeronautics and the raising US dito as a beacon of enlightenment seems a bit simplistic given that the US fielded a TRANSPORT aircraft at this time that was actually longitudionaly UNSTABLE in some flight conditions: The Douglas DC-3 was with normal rated power and also under approach conditions statically UNSTABLE. See NACA TN 3088 (Can be downloaded from the NASA NTRS server) page 31 figure 5. Now compare that to figure 9 page 27 of NACA L-334: The Spitfire FIGHTER shows a NEUTRAL/SLIGHT POSITIVE stability and a better elevator force/speed curve than the UNSTABLE DC-3 TRANSPORT.
While both aircraft undoubtedly would have benefited by a larger margin of stability from a control perspective (logically larger for the DC-3 and smaller for the Spitfire) it is by far easier to overlook NEUTRAL stability in a FIGHTER rather than actual INSTABILITY in a TRANSPORT. Also note that the INSTABILITY inherent in the DC-3 did not stop it from becoming a legendary an popular aircraft held in high esteem by the pilots who actually FLEW them so I think one should be careful before making assertions that the NEUTRAL/SLIGHT POSITIVE stability exhibited by the Spitfire was a serious problem. Another thing to consider is that neutral stability in general means less drag and therefore higher performance and that the pilot can generally more easily transition between high and low speed conditions without retrimming or excessive control forces, both of which are valuable traits in a FIGHTER design.
Finally, I can only second the call to present what is actually wrong with the current Spitfire modeling in CoD: As the saying goes, if it ain't broke then don't fix it. While I readily admit to not having read through the entire 59 pages with a loupe the formulation of the actual problem and what needs to be fixed escapes me.
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