The openings around the aileron mounting brackets. These have long seemed like a potential area for a small amount of drag reduction. I tried a cover on the top side of the outboard mounts some time ago and found that they actually slowed the plane down. I removed them and the speed came back. I thought about that a lot as I sometimes do and rationalized that I had a clear passage from the high pressure bottom of the wing to the low pressure side and it was like holding an open cylinder into the wind then repeating with a cap on the outlet end. I decided that I had to put the block on the entry port and not the outlet. Months ago (maybe a year or more) I installed a barrier at the outboard end on the racing tips.
I'm not sure I measured any speed gain but I have faith that it is an improvement.
Now the inboard end needs attention I think.
I got under the plane and made a cardboard pattern (manila folder stick) and my first thought was to install a thin 0.016 2024-T3 closure plate in there and lap it behind the wing skin and secure it with #4 screws and platenuts and RTV. I made the first part and didn't feel right about it so went home to stew over it.
I decided that a better way to go would be to close the openings with 1/16"x3/4"x3/4" and/or 1/16"x1/2"X1/2" aluminum angle riveted to the aileron mount itself. I made the first part for the inboad side of the inboard mount on the right wing tonight.
Much more to do but for the next two weeks I am going to be overwhelmed with formation training and flying to Reno for the pylon racing seminar.
Bob Axsom
I'm not sure I measured any speed gain but I have faith that it is an improvement.
Now the inboard end needs attention I think.
I got under the plane and made a cardboard pattern (manila folder stick) and my first thought was to install a thin 0.016 2024-T3 closure plate in there and lap it behind the wing skin and secure it with #4 screws and platenuts and RTV. I made the first part and didn't feel right about it so went home to stew over it.
I decided that a better way to go would be to close the openings with 1/16"x3/4"x3/4" and/or 1/16"x1/2"X1/2" aluminum angle riveted to the aileron mount itself. I made the first part for the inboad side of the inboard mount on the right wing tonight.
Much more to do but for the next two weeks I am going to be overwhelmed with formation training and flying to Reno for the pylon racing seminar.
Bob Axsom
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