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Wing Pitot tubing end clearance advice

Randle

Well Known Member
I am slowly finishing the rebuild of my wings and am in need of some advice for the Pitot tubing ends. The plan is to use a Garmin GAP26 heated AoA Pitot tube (Pitot will work with all EFIS manufacturers I am looking at) and leave the AoA tube open for possible future use. I do not have the fuselage yet and would like to run, bend, flare and final fit the tubing before I put the last wing skin on.

The problem: I do not know how much room I will end up with at the wing root during assembly to attach the Pitot tubing to the line from the fuselage. There are many pictures out there on the internet, but none found have helped. I have 1/4? OD Aluminum tubing in the wing for the Pitot tube; will not use flexible line until fuselage. In the picture below you can see a couple of options.

Option 1: After tubing exits the most inboard rib, 90 degree bend the line, flare and connect to fuselage line via union.

Option 2: Use one of the 2 unions shown in the picture, installed in the last rib. I would flare the line between the first 2 ribs and connect it there. The 90 degree union would keep things tight but will it be tight enough, or so tight that I will not be able to easily attach the line to the fuselage side which would require me to use the straight union?


On the inside of the wing, I am planning on bending the line 90 degrees aft where the B-nut and ferrule is, and terminating it with the 90 degree AN fitting shown in the picture below to connect to the Pitot tube. Any foreseen issues there? The pitot line in the picture is touching the bellcrank, but that will be bent to clear any chafing possibilities.
 
Although I ran a Dynon pitot heated prob, i found out that younhave about 3 1/2 inches where the fuel lines hook up and where the pushrod enters the fuselage is about an inch less. I left my lines long and ran them with an inside the fuselage where I have an adel clamp and disconnects for all wires and lines.
With your hard line pitot tube you could put a bulkhead fitting on the side on the fuselage to connect to provided you did a small loop to allow for any flex which I guess would be minimal. .
With all the wires from the heated pitot, the nav, strobe and landing and taxi lights and the two lines from the Dynon pitot tube I needed more access through the side of the fuselage. I called Vans to see if I could put in extra bushings to accomidate them.. I was told two maximum additions but keep the hole spacing and edge spacing requirements between the bushings,

When you get to your fuel lines some builders put an inline filter in the space between the wing and fuselage. This eliminates fuel spilled when changing out the filter inside the aircraft.

Jack
 
I recommend you terminate the hard line at the inboard inspection panel bay and plan to make the connection to the cabin plastic tubing at that point. You will have more room to work with your hands there.

In regards to the connection, I used all hardware but many have simply used 1/4" ID hose slipped over the aluminum and plastic tubing (and clamped) with years of success.
 
Still unsuccessful in finding a good picture of the root area. As for now I think I am just going to have to bend and flare the line for the pitot connection and leave the pitot line a little long at the root until I get to see someones build or a good picture. I would really like to have the connector in the root for ease of maintenance during wing removal and install. I want as few connections as possible. Anything you may find or can share will help.
 
There is a reason you don't find a good picture of the area you are envisioning. It does not really exist.
It is very tight right behind the spar. Nobody is going to try to take pictures of it because they have discovered (either before or afterwards) that its a terrible place to put a connection. You can get your hand in there. Flat. And then do absolutely nothing with it nor get a wrench in. You will need to snake the wires into the cabin before fully inserting the spar.

The area in front of the spar with the gas tank is a different story. Plenty of room. Don't let that fool you into thinking its the same way behind the spar.
 
its a terrible place to put a connection. You can get your hand in there. Flat. And then do absolutely nothing with it nor get a wrench in. You will need to snake the wires into the cabin before fully inserting the spar.

That's what I was waiting to hear. I have seen many pictures of extra length of line hanging out of wings but none of interface connection.

Any advantages in making the connection in the first inspection panel over under the seat or in the cockpit?
 
Bill is dead on - there is no room aft of the spar and I learned it after the fact (ugh!). Have rerouted everything through the area just behind the spar or in front. With the RV6 there is access just after the spar through the opening for the aileron push tube (be careful not to cause interference) or in the lower or upper corner just after the spar.
All my connections are under the seats except the fuel which is up front. Others may do it differently.
 
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