Quote:
Originally Posted by Ataros
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"Working as intended, historically accurate. (updated by Ilya "Luthier" Shevchenko and Roman "Mad Dragon" Deniskin) "
I cant believe that as accurate. I am yet to see any ASI behave in this manner including on some relatively ancient types. Given we are talking about basic Pitot static devices in both RAF and Luftwaffe types why should the only the RAF ASI exhibit this behaviour ?
This DVD
http://www.amazon.co.uk/Supermarine-.../dp/B000AOX79M
Contains some exceptional in cockpit over the shoulder imagery of a MKI being test flown. This includes a a full low level aerobatic routine in which the ASI can be clearly seen.
There are NO wild reductions in IAS as G is applied. You do see normal IAS reduction as the speed varies throughout the manoeuvres but you don't see ASI needle reductions/fluctuations responding to G/backstick increases.
Here is a screen grab to illustrate the view presented in the DVD test flight the ASI is clearly visible throughout:
And another DVD with Cockpit Cam showing a display routine in a Hurricane I
http://www.amazon.co.uk/ITVV-Hurrica.../dp/B0036U2VGW
Its cockpit viewpoint shown in this screen grab:
Again NO large ASI swings under G/Backstick. Some minor oscillations in the order of +-5MPH max are evident.
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In the case of large Yaw inputs (particularly at low IAS) then some small oscillation could be expected since the Pitot head on the RAF types is located on the outboard section of the wing. (Port wing in the Spits case) therfore the pitot head would experience local airspeed changes with yawing. e.g. If the YAW input results in the pitot head "advancing" into the airstream (On the Spit with the Pitot head on the outer port wing yawing RIGHT) then you could expect a momentary minor increase in IAS. Once the YAW stabilises the ASI would be constant. The opposite being the case if the yawing moment results in the pitot head retreating in the airstream (in the case of the Spit Yawing LEFT). This is one of the reasons why with aircraft with Pitot heads on the outboard wings that you see differing stabilsed IAS values in a spins to Left and Right.
There is no rational reason imo why this should occur in the pitch axis.