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pitot and static testing with digital manometer?

rv8ch

Well Known Member
Patron
Does anyone have any experience using a digital manometer to test the static and pitot?

I see a bunch of devices on Amazon, but not clear to me what pressure ranges I should select, if they are accurate enough, can they measure a vacuum, etc.

I did some testing using the water tube method, which worked ok, but quite a hassle to set up.

Thanks for any tips!
 
Here is a simple rig to check for static leaks. Harbor Freight parts and some assembly. I just used this on the new RV-8 project to verify the system tight - and sure enough found a fitting not well seated. A few minutes later it was fixed and saved me the pain of paying to get a failed pitot/static check.

Credit goes to Tom Doran (N716RV)

For pitot I use a $4 manometer to verify airspeed accuracy and pitot line tight. This setup is amazingly accurate. Use google to find the PDF file for the airspeed grid.

Carl
54271407-446-C-49-F1-9-AE5-2-EDCCCEB99-F0.jpg

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static pitot test

Thanks Carl. I was hoping to find a digital manometer that I could use to test the static and pitot over a range of known pressures which should line up with altitude and airspeed values.

This is required for my aircraft certification here in Switzerland. I've done several tests using water in tubes, but wanted to take this into the digital age. :D

Also, the water head required to test the static to an altimeter reading of 20'000 ft is about 21 ft if my math is right. :eek:
 
I had a vacuum line leak in one of my cars after doing an engine swap. For the life of me I couldn't find the leak until I came up with the idea of throwing a lit cigar into a coffee can. The lid had two hoses attached, one ran into the intake taped off with a judicious amount of duct tape. The other was ran into to a pressure regulator turned all the way down and connected to shop air. The very slight pressure pushed the smoky air into the intake which revealed the leak in short order.
 
Thanks Carl. I was hoping to find a digital manometer that I could use to test the static and pitot over a range of known pressures which should line up with altitude and airspeed values.

This is required for my aircraft certification here in Switzerland. I've done several tests using water in tubes, but wanted to take this into the digital age. :D

Also, the water head required to test the static to an altimeter reading of 20'000 ft is about 21 ft if my math is right. :eek:

If you are trying to calibrate the altimeter, none of these devices will be accurate enough. If you are doing a sanity check, you need to look at the specs on the test instrument to determine what accuracy you can expect. Mechanical gages that are cheap are 2% or more of error.
I don?t think you will find a commercial digital manometer will indicate directly to altitude though, you will need to correlate pressure to altitude using FAA 14CFR Part 43 appendix E.
 
The most accurate digital or mechanical manometer you will find (other than a proper test-rig) is the altimeter in the plane. So anything less than a formal pitot-static test rig is a waste for anything other than a leak-check.
 
test rig

The most accurate digital or mechanical manometer you will find (other than a proper test-rig) is the altimeter in the plane. So anything less than a formal pitot-static test rig is a waste for anything other than a leak-check.
Seems like you are right - lots of things are changing all the time, so thought this might be an area for some innovation, but I guess not quite yet!
 
The most accurate digital or mechanical manometer you will find (other than a proper test-rig) is the altimeter in the plane. So anything less than a formal pitot-static test rig is a waste for anything other than a leak-check.

Well, a water manometer is at least as accurate, if not more so, but as someone pointed out you need something like a 20' U-tube to set one up to test to full altitude. So not really practical.
 
Here is a simple rig to check for static leaks. Harbor Freight parts and some assembly. I just used this on the new RV-8 project to verify the system tight - and sure enough found a fitting not well seated. A few minutes later it was fixed and saved me the pain of paying to get a failed pitot/static check.

Credit goes to Tom Doran (N716RV)

For pitot I use a $4 manometer to verify airspeed accuracy and pitot line tight. This setup is amazingly accurate. Use google to find the PDF file for the airspeed grid.

Carl
54271407-446-C-49-F1-9-AE5-2-EDCCCEB99-F0.jpg

Carl, how does the black tube from the syringe connect to the static port? I don't imagine a simple suction cup will seal over the pop-rivet static port. It looks like the dual suction cup lift handle is just a support to hold the tube in place?
Does the dual suction cup lift clamp down enough to push the end of a rubber tube up tight against the static port?
 
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The suction cup is a standard one you can find at most hobby stores, Walmart, etc. Drill a 1/4? hole through the center of the cup, slide in a piece of 1/4? tubing and add some RTV to make the seal. Drill a 1/4? hole through the suction cup holder for the tubing. Now add a spring between the suction cup and the holder to press the suction cup against the fuselage. Add a rubber hose to the tubing and then your suction source of choice.

Carl
 
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