On Feb 20, 10:36*am, wrote:
On Feb 20, 8:35*am, jcarlyle wrote:

Probably what's happening is that the weather sealing around the vent
flap has failed, leaving a small gap when the vent is closed. Have you
checked the sealing of the vent when it's closed?

-John

I'll check that seal if I can. *I'm going to try an re-create the
issue on the ground with a shop vac or leaf blower. *Of course I might
not be able to hear the vent noise over the motor then :-)

It's not the canopy seal. *That used to whistle right by my ear until
I replaced the seal and added foam.

Thanks
Todd

Todd,

When I had my problem, it was the same symptom as yours. When I opened
my vent, the howling noise subsided. When closed, it came back...loud!
Once I sealed the canopy up front, the noise went away and the vent no
longer had any effect (other than the minimal noise from the incoming
air). The only thing I could come up with to explain this is the vent
was having some effect on the pressure differential between inside and
outside of the cockpit. Although I could be wrong on that. All I know
is sealing the canopy fixed the problem.


Dave