On Saturday, October 12, 2019 at 9:42:44 AM UTC-6, Armand Charbonneau wrote:
My Ventus 2c makes a howling sound when flying at 0 flap setting. It is significantly less noticeable immediately after changing the flap setting either positive or negative. Pilots tell me they can hear it when flying overhead or landing. I can hear it seemingly behind me, inside the cockpit. Gear up or down does not seem to make a difference.

The glider was refinished with poly in 2012, so I suspect the wing seals are seven years old. Otherwise the ship in very good condition and soars nicely.

Does anyone know what could be causing this sound? I can replace all the seals this winter, but they appear to be in good condition, except maybe on the tail plane.



Update: I put foam in the top of the tail to block wind from going out the horizontal stabilizer/elevator. The interior air flow is now channeled out the bottom of the tail where there are openings for the rudder cables. While the noise is not gone, it is significantly diminished especially at 0 flap settings. I plan to change all the seals this winter, ensure the canopy is not drafty, and try the straws in front vent method mentioned in this tread.