I am using a 4 inch diameter duct from the tail plenum in my L-IVP to cool my A/C condenser and would like to include a selonoid operated shut-off  to reduce the drag of the plenum air while in flight.

In my original design, I used a divertor box from a clothes drier exhaust;  which proved to be too light weight so I am looking for something a little heavier.  Anyone have any ideas or suggestions????

You can contact me directly at:  billhogarty@direcway.com   THANKS