jamesm Posted September 7, 2019 Report Share Posted September 7, 2019 I am in the process in compiling with SI M20-43 which relocates the static source tee fitting (the plane was originally delivered the TEE is located on the left side static port) that the that the feeds static system. The SI relocates the TEE to near the top of fuselage in the tail section. I have taken the aluminum tubing static assembly home to do a leak test it before installing it. The SI calls out the compression fittings but seems like a real PITA to make these compression fittings not to leak. After watching a few You tube videos and I am seeing how leak pron the compression fittings can be. I have looked in the AC43-13-1B and other sources to see if there some information "approved/ acceptable" fittings for static lines. AC43-13 talks about static testing but I didn't see anything that talks about specific fittings to be used for static lines. I don't remember covering this topic in A&P school either. I ask an IA about "approved" fitting for the static /pitiot lines. and agreed there is nothing that states specific fittings to be used for static lines on certified aircraft. I see that experimental guys are using PTC (Push to connect) versus Compress fittings. Seems like a much better solution. Is there something that I am missing on my fitting dilemma or am I over thinking this? TIA, James '67C Quote Link to comment Share on other sites More sharing options...
Yetti Posted September 7, 2019 Report Share Posted September 7, 2019 Mine has all plastic fittings and plastic tubing back to the ports. Things I know about the plastic fittings is that there is too tight and too loose. Some need new o rings each time you open them. Just right tight is finger tight and about an 1/8 turn with a wrench The push fittings are really cool. Pretty much what all pneumatic stuff uses nowdays. So if that industry standards is applicable to airplanes, and you can pass the static test, and your IA is comfortable signing off on your sign off Not an AP or anything. Happen to work in the controls industry Quote Link to comment Share on other sites More sharing options...
jamesm Posted September 7, 2019 Author Report Share Posted September 7, 2019 The service instruction covers all M20 series and specifically lists M20C's and some of the earlier SN's of the M20J's & M20K's Models it publish in 1979. is it all plastic even between the static button ports on sides of the fuselage on the M20F models ? or did it get converted to plastic along the way ? Could they use the plastic fittings with the specific union and tee fittings called out in the service instruction ? I thought those fittings are used with 3/16" aluminum tubing? Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted September 7, 2019 Report Share Posted September 7, 2019 I replaced all my static lines a few years ago. I was always having a hard time passing the static leak test. The plane had polyethylene tubing. I replaced it all with nylon and new fittings. It has been solid ever sense. https://www.aircraftspruce.com/categories/aircraft_parts/ap/menus/ha/fit_znylo.html Quote Link to comment Share on other sites More sharing options...
Andy95W Posted September 7, 2019 Report Share Posted September 7, 2019 @jamesm- I just did this SI on my M20C this year. I used the Nylo-seal fittings that Rich referenced above as well as an additional brass fitting for the connection to the existing components. I didn't worry so much about the exact part numbers listed in the SI, I just made the installation look like the one in the picture. My logbook signoff was that it was a minor alteration, noted the approved parts, and my data was the Mooney approved service letter drawing. The Nylo-seal fittings are very good. They have to be good and snug, but not monkey tight. They seal very well. Quote Link to comment Share on other sites More sharing options...
jamesm Posted September 7, 2019 Author Report Share Posted September 7, 2019 How did you make the conversion off the static port button? So aren't the fittings from the static port buttons very short aluminum tubing then brass union (62X3). is there way come off the static port button directly into a nylo-seal fitting(s) ? Thanks for all the great advice. James '67C Quote Link to comment Share on other sites More sharing options...
jamesm Posted September 7, 2019 Author Report Share Posted September 7, 2019 so is the polyethylene tubing = ploy-flo (slightly soft) ? nylon tubing = nylo-flo (rigid stiff compare to ploy-flo) ? Nylo-seal v nylo-flo tubing ???? Quote Link to comment Share on other sites More sharing options...
Andy95W Posted September 7, 2019 Report Share Posted September 7, 2019 I used the nylo-seal tubing. My 1964 doesn't have the drain, so that made that part simpler. Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 8, 2019 Report Share Posted September 8, 2019 On 9/7/2019 at 5:44 AM, jamesm said: I am in the process in compiling with SI M20-43 which relocates the static source tee fitting (the plane was originally delivered the TEE is located on the left side static port) that the that the feeds static system. The SI relocates the TEE to near the top of fuselage in the tail section. I have taken the aluminum tubing static assembly home to do a leak test it before installing it. The SI calls out the compression fittings but seems like a real PITA to make these compression fittings not to leak. After watching a few You tube videos and I am seeing how leak pron the compression fittings can be. I have looked in the AC43-13-1B and other sources to see if there some information "approved/ acceptable" fittings for static lines. AC43-13 talks about static testing but I didn't see anything that talks about specific fittings to be used for static lines. I don't remember covering this topic in A&P school either. I ask an IA about "approved" fitting for the static /pitiot lines. and agreed there is nothing that states specific fittings to be used for static lines on certified aircraft. I see that experimental guys are using PTC (Push to connect) versus Compress fittings. Seems like a much better solution. Is there something that I am missing on my fitting dilemma or am I over thinking this? TIA, James '67C Your observation is correct... Compression fittings are an experienced based system... It takes a simple training to get them right... It is hard to know if you are doing them incorrectly... Mixing parts from different suppliers is a common mistake... The pitot static system is a crummy place to have somebody learn the technology... the O2 system is a similar crummy place to learn... PP thoughts only, best regards, -a- 2 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.