Shower curtains, too...

On 7/15/2019 6:47 AM, wrote:
I've never tuned a glider, but before I bought my glider I read all of Dick Johnson's test flight reviews. As others have said sealing the control surfaces is where Dick saw some of the biggest returns, but he also would seal the wing roots around the control rods to prevent the (relatively) high pressure air in the fuselage from venting out through the top of the spoiler box and push rod exits. I've seen people do this with cones made of Ceconite and heard of large balloons being cut down and used as well.
DT

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Dan, 5J