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Jinkster
4th May 2004, 18:09
Oh no not the Jinkster asking for help again you may say....I am afraid I am.

Which is one of the disadvantages of increasing the number of propeller blades?

1)

a) Increased noise
b) Less power can be absorbed by the propeller
c) Higher tip speed
d) Decrease propeller efficiency <-

'Surely this is wrong!!' I would suggest (a) myself but this is what my feedback is saying!

If you increase the propeller pitch during a glide with idle-power at constant IAS the lift to drag ratio will?

2)

a) increase and the rate of descent will increase
b) decrease and the rate of descent will decrease
c) decrease and the rate of descent will increase
d) increase and the rate of descent will decrease <-

SHOULD THIS QUESTION BE JUST ‘PITCH’ AS APPOSE TO PROPELLOR PITCH??

Many thanks,

Jinkster

redsnail
4th May 2004, 19:39
Jinks,
Not quoting from any texts but from experience.
The first one,
No, flown a 2 bladed C207, noisy as, flown a 3 bladed C207, quieter.
Second one, it's the size that can absorb the power.
Higher tip speed, no, more blades = slower = less noise.