Aircraft Propeller Nicks

[Stache]

How come when you walk up to the front of an airplane, the front of the propeller is nice and clean? It has almost no bugs or nicks or dings. But the back side, the side you look at from the cockpit, usually painted black, has all sorts of nicks and dings in the paint. What gives?

Can someone explain this in layman terms?

Stache

 

[IRstuff]

The things that scrape paint are usually hard object such as dirt and rocks. This occurs when the plane is near or on the ground and is not moving forward very fast. Rocks moving toward the front of the propeller have low probabilities of actually hitting the trailing part of the propeller, since it's moving sideways faster than the plane is moving forward. Things that are past leading edge of the propeller will tend to get caught and scrape along the backside for the same reason as above.

TTFN

 

[berkshire]

The particles entrained in the air have too much mass to react to the rapidly changing direction of the airstream as the propellor blade approaches.
They only change direction significantly after the blade has hit them.
B.E.

 

[MikeHalloran]

... and because of the blade's angle of attack, it's the black/ back/ flat side of the blade that is most likely to hit them.



Mike Halloran
Pembroke Pines, FL, USA

 

[berkshire]

Thank you mike,
I meant to say that.
B.E.