Whistles while it works

[damonb]

I have noticed my 152 develops a whistling sound at high rpms. I have heard something like this before with vacuum lines on cars. However I am developing good vacuum. So if it is a vacuum leak, it is a small one.

Another possibility could be a leak on the air intake. However the engine is developing good power. So if it is the source, it is a small leak.

Are there any other possibilities that could be causing the whistling noise?

 

[AWACSEng]

The blistering speed of the mighty 152? Sorry, it was going to be said by somebody. Is this in flight or on the ground?

 

[damonb]

The blistering speed of the mighty 152? Sorry, it was going to be said by somebody. Is this in flight or on the ground?

The last time I looked under the cowling I was pretty sure I did not see a turbo.

I hear it both in the air and on the ground. It does not seem noticeable on taxi, but I can definitely hear it from 1500 rpm on up. It seems to be pretty constant.

 

[RotorAndWing]

The last time I looked under the cowling I was pretty sure I did not see a turbo.

I hear it both in the air and on the ground. It does not seem noticeable on taxi, but I can definitely hear it from 1500 rpm on up. It seems to be pretty constant.

You might be hearing the air coming through the wing root vents. Try adjusting them and see if it changes.

 

[N801BH]

very possible it is a vacuum leak in a line going to one of your gauges, the higher you rev the motor the more vacuum you get. Well, till the vac reg limits it.

IMHO.

 

[Tom-D]

What you are hearing is the disk in the vacume regulator vibrating, They whine like a reed in a musical instrument.

 

[Ddayle]

all 150 & 152's make that sound as they approach Mach one.

 

[Kelvin]

I have noticed my 152 develops a whistling sound at high rpms. I have heard something like this before with vacuum lines on cars. However I am developing good vacuum. So if it is a vacuum leak, it is a small one.

Another possibility could be a leak on the air intake. However the engine is developing good power. So if it is the source, it is a small leak.

Are there any other possibilities that could be causing the whistling noise?

"Squawks" are problems noted by U.S. Air Force pilots and left for maintenance crews to fix before the next flight. Here are some actual maintenance complaints logged by those Air Force pilots and the replies from the maintenance crews.

(P) = Problem (S) = Solution


P: Unfamiliar noise from engine.
S: Ran engine continuously for 4 hours - noise now familiar.