Installation of AOA Pitot Tube

logansc · #1 12-29-2016, 06:58 AM

I'm installing a new AFS/Dynon AOA-enabled pitot on my 7 year old Rocket. There does not seem to be an obvious way to string the additional pitot tube and wiring necessary through a long finished wing with only two small inspection plates. Complicating matters is the fact that Rocket wings fit pretty tightly to the fuselage with little space between the two. My wingtip antenna, landing light, strobe, etc wires were strung in the open through small rib holes with plastic grommet inserts. They are ty-wrapped by not otherwise protected or inside a conduit. Nevertheless that route is full with no more room (don't see how I could use them anyway.

Anyhow, long story short, has anyone figured out a safe/suitable/clever way to get the new lines (pitot and signal) out through the wing to the new pitot?

Thanks!

Lee...

dtw_rv6 · #2 12-29-2016, 07:31 AM

I'm not really familiar with the Rocket limitations, but I used electricians "fish tape" to run the additional tube and electrical to my Dynon probe. My wing/fuselage clearance is very tight, and I had to do some contortions below the seat once I got it into the cabin, but the wing routing was the easiest part...

Hope that was helpful.
Don

bret · #3 12-29-2016, 07:54 AM

Can you pull your 1/4" Pitot line and replace it with two 1/8" nylon air lines? I think the tubes in the Dynon AOA are 1/8" to begin with.

TS Flightlines · #4 12-29-2016, 06:49 PM

Our solution was, "unique"
Tom

Chkaharyer99 · #5 12-29-2016, 07:14 PM

Quote:

Originally Posted by TS Flightlines

Our solution was, "unique"
Tom

Please, do tell.

flyboy1963 · #6 12-29-2016, 08:36 PM

Quote:

Originally Posted by TS Flightlines

Our solution was, "unique"
Tom

...could it be....

pulling an 1/8" INSIDE the 1/4"?????

ok, on second thought, impossible to terminate that in a useful way.....

sounded good on paper ( the stuff between my ears!)

Raymo · #7 12-30-2016, 05:49 AM

Quote:

Originally Posted by Chkaharyer99

Please, do tell.

We used a long aluminum tube (Lee's idea) extended with some aluminum angle (Tom's idea) and ran the AOA tubing through the aluminum tube to the root where Tom guided the AOA tube through the new hole into the fuselage.

Vac · #8 12-30-2016, 07:22 AM

I just retrofitted a Dynon tube to my -4 last Spring, and there is a good write-up in the RV-4 section by Randy. Here's the link:
http://www.vansairforce.com/communit...ght=pitot+tube. I'm unfortunately not familiar with the F-1 fuel tank configuration, and if it's completely different than the RV-4, unregard! If it's similar, removing the tank might the the trick.

Pretty straight forward with the tank removed. I used the Gretz mount as I thought the larger flange was beneficial since I couldn't tie into the adjacent rib. A small bucking bar and riveting is a one-person job. The trick to pulling the tank is to use cheap plastic signs to slip under the flange as the nested countersinks do a remarkable job of holding the tank in place! Not an issue if your tank screws are countersunk. A paint cutter is helpful on the screws, and I just painted the replacement screws to match the original colors in lieu of using the original screws. I ran the heater wiring and installed an additional OAT probe for my engine monitor in the old pitot hole in the wing when I ran the new pitot plumbing.

I did learn one lesson (if your fuel sender is in your inspection plate): if you have old-fashioned resistance type fuel senders, don't ever try to loosen the screw attached to the wire...cut it and splice the connection when you are finished with the job. In many cases, those screws are over-tightened or seized; and if you rotate them, you can break a solder joint on the inside of the sender. This will require you to remove the inspection plate, replace the sender and reseal. If you hated pro seal the first time, you'll like it even less later on...

It's a nice retrofit, and with all of the modern avionics requiring multiple pitot/static/aoa connections, I've just built a manifold for each behind the panel with the quick disconnects that Stein sells. Makes maintenance and modifications easier.

Good luck and don't hesitate to drop a line if you'd like more info!

Vac

TS Flightlines · #9 12-30-2016, 08:11 AM

Mike---we didnt want to pull the tank, OR remove the upper skin

.
We had a piece of 3/8 .035 that the tubing fit inside, so we removed the wingtip and pushed the tubing through some lightening holes to a new hole in the fuselage. the 'unique' part was getting 6 foot piece of tubing to reach the entire distance we needed. Thats were the 'extension angle' came into play. WE thought that someones arms were going to be long enough to reach what we needed, but naaaa. So we improvised and made special rocket tool number 115!

Tom

Chkaharyer99 · #10 12-30-2016, 10:14 AM

Quote:

Originally Posted by Raymo

We used a long aluminum tube (Lee's idea) extended with some aluminum angle (Tom's idea) and ran the AOA tubing through the aluminum tube to the root where Tom guided the AOA tube through the new hole into the fuselage.

I'm trying to picture this.

I want to add AoA to my RV-8. It has the old school homemade pitot. I have a new Gretz and plan to buy a Garmin Pitot with AoA. My wing currently has only the one tube for Pitot. I will have to add the AoA tubing.

Did you place the AoA tubing in the lightening holes?

Maybe you have a few photos you could share.

Thank you