Stability and Control characteristics of the Early Mark Spitfires

[MiG-3U]

Originally Posted by bongodriver

By how much? I think you will find the CoG is probably different because there are no guns or ammo, anyway the point is proved that you were wrong and 'no' modifications such as you claimed were carried out.

Thanks for posting the CAA links!

The CoG limits are exactly the same as given in the revised manual for the standard elevator without inertia device and with DeHavilland propeller. At normal service load the CoG was around 7.7" aft datum point so there was no need for the bob weight. Without the seat armour and weapons the CoG is of course even more forward.

However, the NACA tested Spitfire had the Rotol propeller which was more sensitive for the CoG due to lighter blades, hence the aft limit was 7.5" aft datum point without bob weight and NACA had the CoG at 7.8". In other words such loading was not allowed without bob weigh according to revised CoG limits. Also the Spitfire II manual quoted many times here is for the Rotol propeller, hence the warnings before the CoG limits were revised. The manual for the DeHavilland propelled aircraft and the later revisions, after the CoG limits were revised, do not contain such warnings.

Now, we have here about 70 pages of some members (apparently all from blue side for one reason or another) demanding that the stability and elevator control of the early Spitfires should be modeled according to the worst case scenario; Rotol propeller and the CoG behind the limits for such combination

BTW wasn't there some one claiming that the all currently flying Spitfires have the bob weighs?