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Old 7th January 2007 | 20:19
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helopat
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From: Australia
Originally Posted by mderdem
Hello,
It is your simulationist again. This time my question is about how successful the pitot-tube based IAS measurement for rearward and sidewards flight is ?
Since the inlet of the pitot-tube points to forward, it is surprising for me if sidewards speeds can be measured correctly as good as forward speeds. Can the IAS reliably measured when helicopter is hovered rearward or sidewards ?
Thanks!
MDE
I think that the most important differentiation to make here is airspeed (measured by the pitot-static system) and ground speed (measured by eyeball, or in a more complex aircraft, by a doppler radar system)...the doppler groundspeed is usually indicated on a digital display.

The pitot system is quite unreliable at low speeds and not reliable at all at measureing sideward or rearward flight. Forward flight below 25-30 kias is not reliably indicated.

Hope this helps.

HP
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