outside air leaks in cockpit

I have been trying isolate the air leaks in my cockpit which let cold air in during high altitude flying in my 6A. So far I have found two. One is the fresh air vents themselves, and the second is from the stick area. At the control stick the air comes up through the boot and blows on me.

Is this normal in an RV? How can I improve this situation?

I have a cabin heat which works but seems to be much less effective due to the leaks I've mentioned here.

I live in SoCal so cold weather is not too much of an issue. However, if I were to say take a cross country flight to a mountain resort in winter, it might become one.

Any help would be appreciated.

Some guys also have boots installed where the aileron pushrod passes into the fuselage. Don't know if that helps you.

Here's Sam B's excellent article on the topic:

http://home.hiwaay.net/~sbuc/journal/cold.html#boots

arffguy said:

Some guys also have boots installed where the aileron pushrod passes into the fuselage. Don't know if that helps you.

Click to expand...

Oh ya it helps a great deal. Installing boots around the aileron to fuselage point was the single largest improvement in cold weather flying that I have made to date.

the only change from Sam's instructions is that I simply bought some Tyvek painters coveralls at Lowes and cut a section of the sleeve off. You simply slip the wrist cuff over the tube and glue down the ring to the arm part and you have instant sealed bellows with no sewing, or making a tube etc. Very easy! Then I simply used a plastic zip tie around the aileron tube to hold the cuff in place and pop riveted the ring to the fuselage side.

Thanks for the help again

I read all the replies and links and now have some direction toward working on this problem. I'm not the builder so I doubt that I will try removing the wings to seal the aileron push road to fuselage hole. I will look at what I can do from inside the cock pit. I have taken some of the floor panels off for a condition inspection so maybe I'll start there.

Thanks again.

You got it. All of this can be done from inside by removing the seat pans.

European style boot

I bought the European style boot from JC Whitney and made a aluminum ring and riveted them to the outside of the fuselage. Works great no air whatsoever.

http://www.jcwhitney.com/autoparts/ProductDisplay/s-10101/p-5647/c-10101

Works

After reading this post I went ahead and did the mod. I can't believe the difference!!! I live in Utah and all my trips are at 11,500 or 12,500 msl. With the cold Utah winters, I find that my heater can barely keep the passenger warm and I freeze, particuarly my hands. Well, not any more... -15c @ 13,500 for 3 hours and the heat was on half the hole time, full blast was too hot. I love it! I did the entire project in about 6 hours with the help of one friend and that includes running to the fabric store, sewing the cones, cutting the aluminum, and stopping for Wendy's. It's the best mod I've made since GPS and Auto Pilot. THANKS FOR THE TIP!!!

don't forget the spar entry holes

There's also a sizable hole left in the fuselage side after you insert the spars (on the 7 and 9, at least). Although there isn't as direct a path for the air to leak from within the center box spar out the stick boot holes, there is still a path there.

I'm going to add some closed-cell foam to that hole during my annual to try to seal things up even better.

--Clay

Are the wing spar holes a problem on the 6A as well? I'm looking for more upgrades, can't get enough of this thing. Good thing my wife is a pilot as well or she would get sick of all the time I spend with that plane. I logged over 500 hours in the last 12 months; smiling the entire time... dang my cheeks hurt.

Air vent fix

Here's a tip for the leaks around the air vents.

Rough-up the back side of the vane part so it will take paint, then smear the inside of the vent tube with vaseline. If you've got big gaps, you might have to use some masking tape on the front side of the vane. Get some of that "Plasticote" vinyl-in-a-can spray paint and spray the back side of the vane with it shut, to form an air-tight seal. Be sure to let it dry face-up so the vinyl runs down around the vane. The vaseline will keep it from sticking to the tube.

Ken Scott's Article in October 2003 Sport Aviation, etc.

1 - Ken Scott of Van's Aircraft wrote an article about aileron pusrod boots in the October issue of Sport Aviation. "Baby Gets New Booties" is on page 97 of my copy. I used ripstop nylon as he describes in the article and the difference is great.

2 - I have an "A" model and good upper fairings on the main landing gear struts are important there to cover all the brake line and gear leg holes.

3 - Forward side of the spar/fuselage interface should be sealed.

4 - There is a small gap where the fuselage side skin and bottom skin meet just behind the spar web/bulkhead down at the bottom. That should be sealed with some good RTV.

5 - The two plastic fittings at the passenger end of the fresh air ducts should be sealed together with RTV.

6 - A little tapered square cap should be made to cover the track opening at the rear of sliding canopy skirts.

7 - A small follower plug should be made to be pulled with a piece of nylon lacing tape (string) tied to the the rear bracket bolt to close off the hole under the hat in "6" above when the canopy is closed. Small sections of white "P" strip from Aircraft Sprucecemented to the plug give a good seal but the string has to be the right length to pull the plug in and not interfere with the canopy closure back there.

8 - Small aluminum straps pop riveted to the canopy frame and solid flush riveted to the side skirts help to keep those aligned (George Orndorff welded his to the frame).

9 - 3/4" aluminum angle turned up and riveted to the upper longerons between the end of the canopy side rails and the upper rear fuselage skin provides a good gap closure overlap without the paint scraping draggy gap closure "tab" called for in this area by the drawings. The rear closure pins naturally drop down inside the angle and go home in the anchor blocks with no interference.

10 - (This is the best thing I did for more reasons than just sealing the cockpit) Make a rib of 3/16" bar stock that runs the full length of the canopy side rails and perfectly conforms to the fuselage mold line (use file folder stock to make patterns for each side - tape them down and trace the fuselage outline on the underside at the edge of the canopy deck) - hack saw and file if you have to like I did - it is worth the effort. When you have them shaped properly use all the proper techniques to double flush rivet them to the side skirt in a way the will not interfere with the windshield roll bar upon closure at the maximum outward extension of the side rail radius. Use the patterns to make sealing surfaces of rubber sheet and glue them to the underside of the ribs so that when the canopy is closed the straight edge of the rubber seal slides smoothly along the only straight constant interface surface between the fuselage and the canopy - the one provided by the new rib and the canopy roller extrusion. In addition to provoding a sealing surface it eliminates the characteristic sliding canopy side skirt suck out due to low pressure in this area in flight.

11 - Cement on white "P" strip an appropriate sealing set back from the edge of the aft canopy skirts.

12 - Apply silicone between the end of the white "P" strip and the side skirt rib where the gap is too small for anything else and and close it on a waxed or lubed fuselage surface to get a perfect gap fill fit in this area.

13 - Cement white "P" strip on the upper edge of the roll bar where it mates with the fiberglass windshield bow/flange that overlaps the leading edge of the canopy when closed.

14 - Finally, very carefully apply the expensive aluminum tape from Aircraft Spruce (around $50 per roll as I recall) to cover the pop rivets and shims etc, at the leading edge of the sliding canopy - roll it down over the front of the plexiglass in this area cutting as required to avoid wrinkles and carefully trim off the excess. It will wear out after a while but and hour's careful work has it replaced and looking good as new.

It ends up being a very high quality airtight canopy installation.

Bob Axsom
60062/N710BJ

pics?

Bob,

Do you have pics of #10 in the above post? I am trying visualize it. I assume that this method would also work on the 8.

Has anyone else developed a way to seal the canopy along the side rails/skirt area?

Thanks,

Tony