To: Rotorque
It seems that your instructor was wrong in addressing Alpha Angle and I too was wrong in my interpertation of your post. Here is the explanation of Alpha Angle straight from the "Horses Mouth", MBB in Germany.
"Generally, alpha angle - the angle of attack - is defined as the angle
between an airflow (relative wind)
and the reference chord (a line drawn between the leading and trailing
edges) of an airfoil.
This airfoil may be a wing or a rotor blade.
Alpha is a major factor of lift, the greater alpha, the greater the lift
produced, but - everything has limits -
typically at angles of attack around 20°, the airflow stalls and lift
decreases again.
On many fixed wing aircraft alpha is measured by a little hinged surface
mounted in the nose area
which alignes with the airflow. This angle is indicated on a gauge in the
cockpit.
Alpha is not indicated on helicopters, because the airflow pattern through a
rotor is pretty complicated
and changes constantly. Other values are easier to measure and are displayed
instead.
Hope this is what Your were asking for!
Best regards from Munich!
Diethelm Berndt
Test Pilot
Eurocopter Deutschland GmbH
Phone:+49 89 6000 6065
Mobile:+49 171 7341699
Fax: +49 89 6000 6622
E-mail:
[email protected]
-----Ursprüngliche Nachricht-----
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The Cat