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Any reson not to do it this way? (Pitot connections)

Reflex

Well Known Member
I've noticed that most builders are flaring the ends of the pitot/AOS assembly. I'm wondering if a push to connect is acceptable? I'm using a Garmin GAP-26 heated pitot. According to the installation manual, section 5.3, revision AJ, the minimum length for the tubes on the heated pitot is 8" to protect the non-metallic tubing from excessive heat.

If the tubing is greater than 8", do you see any reason not to use the fittings depicted below?

 
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simpler

I just heated up the tubing with a heat gun, slide it on and safety wired. easy peasey.

I think garmin recommends a distance of the metal before terminating; and this distance is longer than a straight section could be, so the Pitot tubing needs to bend, so the 90 degree fitting may not be the best.
 
As long as your end-fitting can fit through the pitot mast and you can disconnect the tube fitting via the inspection plate, all is good.

I used a straight-run fitting to a ferrule-type connection to the tube, and left a service loop of tubing inside the wing to pull the entire pitot tube and connections down outside the wing and disconnect it that way.
 
I've noticed that most builders are flaring the ends of the pitot/AOS assembly. I'm wondering if a push to connect is acceptable? I'm using a Garmin GAP-26 heated pitot. According to the installation manual, section 5.3, revision AJ, the minimum length for the tubes on the heated pitot is 8" to protect the non-metallic tubing from excessive heat.

If the tubing is greater than 8", do you see any reason not to use the fittings depicted below?


I am not seeing your image but I am using a push-on fitting with the same Garmin pitot heat tube and zero issues. I made sure to adhere to the 8" recommended metal tube.
 
Question?

Sorry. Not meant to be a thread hijack. I haven't found a manual for the GAP-26 and wasn't going to buy the pitot just yet. I assume but pressure sources need to be routed to the cockpit area. Asking because I'll be closing up the left wing soon and sounds like I need to run another soft AL tube and probably dedicated conduit. Any thoughts, ideas, or other suggestions (that would save me from another case of the dumb-***) would be appreciated.
 
Sorry. Not meant to be a thread hijack. I haven't found a manual for the GAP-26 and wasn't going to buy the pitot just yet. I assume but pressure sources need to be routed to the cockpit area. Asking because I'll be closing up the left wing soon and sounds like I need to run another soft AL tube and probably dedicated conduit. Any thoughts, ideas, or other suggestions (that would save me from another case of the dumb-***) would be appreciated.

If Garmin, you will need to run two sot or hard line, most people run soft lines. One is for your pitot tube and one for AOA. The AOA is not absolutely necessary but if using Garmin, then it would be a shame not to plumb that. I can hardly see a reason for a conduit, RV14 and many other models have small holes in the ribs for this usage.

Hope this helps.
 
I just heated up the tubing with a heat gun, slide it on and safety wired. easy peasey.

I think garmin recommends a distance of the metal before terminating; and this distance is longer than a straight section could be, so the Pitot tubing needs to bend, so the 90 degree fitting may not be the best.

Heating up nylo tubing and pushing it onto a fitting will lead to the nylo tube cracking eventually. I've replaced plenty in the static system.
 
Were you able to find a push on fitting for the 3/16? aluminum tubing?

Yes, Legris makes one. Part number 3109 55 11 available at MSC Direct. MSC's part number is 06108591. 3/16 tube x 1/8" NPT elbow.

Spoke to Legris/Parker tech. Fine for aluminum tubing.

About $8.

Fred
 
Sorry. Not meant to be a thread hijack......

But of course that?s exactly what happens when one diverts the conversation away from the OPs question.

I?m also interested if using push to connect fitting to aluminum tubing is acceptable.
 
I have a 90 degree push-on fitting on a Gretz heated pitot and it works fine. Passes the leak check with flying colours.

Jack
 
If Garmin, you will need to run two sot or hard line, most people run soft lines. One is for your pitot tube and one for AOA. The AOA is not absolutely necessary but if using Garmin, then it would be a shame not to plumb that. I can hardly see a reason for a conduit, RV14 and many other models have small holes in the ribs for this usage.

Hope this helps.

Thank you, Sir. Another testament to the great folks here that kindly share their knowledge.

But of course that?s exactly what happens when one diverts the conversation away from the OPs question.

I?m also interested if using push to connect fitting to aluminum tubing is acceptable.

Of course, there are others
 
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My 7 is 15 years old and worked fine with the push on fittings. I'm now changing to a heated pitot (placed further out in the wing)and using the same style push on fittings from Mac-Master Carr including the two 3/16th to 1/4" for adapting AOA and pito hard 3/16 to 1/4". I color coded the static,pitot and AOA lines buying the different colors plastic from Cleveland Tool, which seems to be better quality than the original.
 
errrr......and why not a 3/16" to 1/4" brass compression fitting instead? 5 for $10.

https://www.amazon.com/gp/product/B01N0AYGP6/ref=ox_sc_saved_title_1?smid=A2EZI3G0CWMAWQ&psc=1

Then to Lowes for 1/4" plastic ferrules......

Just wondering.

Great question and I certainly thought about going that way.

For me, the issue isn't price. Brass would be easy to find, inexpensive, and would likely perform adequately.

I'd like to use a push-to-connect (PTC) fitting for the following reasons:

  • I want to be able to remove the pitot tube for inspection/repair
  • My pitot is located a bay outside the bellcrank/inspection panel. A compression fitting requires two tools to tighten or loosen.
  • One of my concerns in looking at installations that use heavier fittings is that the soft aluminum pitot tubes could work harden over time. Haven't heard anything about that, but it appears that any bending of the aluminum tubing away from center or vertical relies on the strength of the tubing to hold the fitting in place. The heavier fitting the greater the possibility of flex in the tubing.
  • The push to connect is lighter
  • Ease of installation
  • Multiple companies use this type of fitting on static ports (Cleaveland, Dynon, Stienair)
 
Great question and I certainly thought about going that way.

For me, the issue isn't price. Brass would be easy to find, inexpensive, and would likely perform adequately.

I'd like to use a push-to-connect (PTC) fitting for the following reasons:

  • I want to be able to remove the pitot tube for inspection/repair
  • My pitot is located a bay outside the bellcrank/inspection panel. A compression fitting requires two tools to tighten or loosen.
  • One of my concerns in looking at installations that use heavier fittings is that the soft aluminum pitot tubes could work harden over time. Haven't heard anything about that, but it appears that any bending of the aluminum tubing away from center or vertical relies on the strength of the tubing to hold the fitting in place. The heavier fitting the greater the possibility of flex in the tubing.
  • The push to connect is lighter
  • Ease of installation
  • Multiple companies use this type of fitting on static ports (Cleaveland, Dynon, Stienair)

Sounds good to me. Thanks for explaining your rationale. As I sit here thinking about this connection (metal to plastic) and what youve said, it strikes me that I might just go and see if a simple piece of rubber vacuum hose will fit both. Add 2 small spring clamps and done. Just thinking....
 
Are the push-to-connect fittings designed to work with metal? Seems like any small scratches might compromise fit/airtightness.
 
Are the push-to-connect fittings designed to work with metal? Seems like any small scratches might compromise fit/airtightness.

John Guest developed the "push-to-connect" fittings in the '70's. they typically use an "O" ring with stainless teeth to grab the tube. Today Push fittings are made of both metal (typically brass), PVC, PEX and polypropylene. Small scratches usually aren't a problem with Guest-style fittings.

-Marc
 
Stein has 2 solutions to connect the Garmin 3/16 in metal to the 1/4 in tubing. Either apush on adapter or combination od brass fittings.
 
Any reason not to do it this way? (Pitot connections)

All my pneumatic connections are made with these push on connectors, 12+ years and no problems. Dan from Reno
 
I'm looking at doing my pitot connections just like the first post in this thread. I'm wondering if the 3/16" tubes from the pitot need to be secured to something to give them additional support or if they are ok to be freestanding out of the pitot tube?

I'm also curious if service loops in the plastic tubes need to be secured somehow. It seems like they probably do need something to keep them from rubbing on the wing skin or ribs and creating a leak but I haven't found any posts that show how people have done it so I'm hoping to get some ideas.
 
What ever you do, plan for removal/reassemble situations in the future - inevitable. That's where fittings from the major avionics suppliers (Stein, Dynon, Garmin, etc.) shine.
I secure any type service loop for sure, protect against chaffing & inadvertant jamming other things.
 
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