High Speed Shaking

[Sternjaeger II]

Originally Posted by Kurfurst

750 kph IAS for 109 (as on all models up to 109K, which increased it to 850), 650 kph IAS on 110.

Different limits were not specified for higher altitudes, ie. it did not decrease with altitude, at least not in the manual (nor did it in 1940 British manuals - although it was only due limited knowledge of Mach effects at the time in both cases, so in reality it was certainly less at altitude). When flutter problems were started to be encountered and people on both sides of the Channel become more aware of it, they tended to decrease VNE at altitude, but left max. VNE near SL the same..

The thing that is odd about the 110 snaking is though that it occurs at low altitudes just as well, at near VNE speeds. If it would be high altitude, I'd understand that its some Mach-related effect.. but its like as if the rudder would be living a life on its own.

Which kinda makes me thing that there are two possibilities:

1. COD has a new hard coded VNE structural dive failure - I have seen similiar on the 109, albeit in much more hairy dives during intentional 'dumb flying', and it sets in earlier because the 110 is limited to 650

2. Engines (props) of the 110 run wildly asyncronized in dive, and this tears the plane apart.

3. Some game controller induced bug with new patch. Curiously, I did have similiar problem with the 2nd beta patch installed, for some reason, my view kept jumping off in the cocpit from time to time without using the HAT switch on the jstick..


What I found annoying though if 1, is the reason, that while no amount of dumb flying (pulling waaay too many Gs with the stick) seem to be able to break the plane, so stupid pilots would not suffer, we may have a rather odd limitation built in by the possible 1. case, which prevents you from even approaching the limits the manufacturers deemed safe yet..!

Kurfurst, flutter is an aerodynamic effect, as such is more pronounced where the air is denser, that is to say at low altitude.
Bear in mind that VNEs are not flutter speeds, they're redundant by a certain percentage (Viperpedia might help us here) and do actually vary according to altitude (modern planes have the so called "barbers' pole" that indicated the KIAS VNE according to altitude).