Empennage hinge fairings

alcladrv · #1 08-30-2009, 04:15 PM

Here are some hinge fairings I saw at Oshkosh. Has anyone used these fairing ideas on their RV? What were the results of using them?

http://tinypic.com/usermedia.php?uo=...IZMIh4l5k2TGxc

Falco

http://tinypic.com/usermedia.php?uo=...ncBoh4l5k2TGxc

Rudder hinge fairing

http://tinypic.com/usermedia.php?uo=...akHYh4l5k2TGxc

Elevator hinge fairing

David Shelton · #2 09-02-2009, 01:27 AM

The hinges themselves are only a small part of the problem. Air leaks through the entire hinge line and causes interference drag. In sailplanes, we first glue an internal dacron seal as shown below. We fold the dacron and create enough slack so the control surface can make full deflections.

Next, we install pre-curved mylar seals over the hinge line (available from www.WingsandWheels.com) like you see below.

Good luck. -David

Ironflight · #3 09-02-2009, 05:58 AM

I think that Bob Axom has tried fairing the elevator hinge points, but I can't remember now if he got good results. You might try searching some of his posts from a while back. As to David's idea of sealing the entire gap, I'd be interested to hear from anyone that has done a complete flight test program with this mod - it is not inconsequential, and can change a lot of control characteristics at RV speeds. I know it is common practice, necessary, and beneficial in the sailplane world, but RV's are not sailplanes - so anyone that tries it needs to be careful!

Paul