VansAirForceForums  
Home > VansAirForceForums

-POSTING RULES
-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.


Go Back   VAF Forums > Avionics / Interiors / Fiberglass > Steam Gauges
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 03-08-2020, 02:19 PM
rv8ch's Avatar
rv8ch rv8ch is offline
 
Join Date: Feb 2005
Location: LSGY
Posts: 4,333
Default pitot and static testing with digital manometer?

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!
__________________
Mickey Coggins
http://rv8.ch
"Hello, world!"
Reply With Quote
  #2  
Old 03-11-2020, 09:08 AM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 3,276
Default

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

Reply With Quote
  #3  
Old 03-11-2020, 01:26 PM
rv8ch's Avatar
rv8ch rv8ch is offline
 
Join Date: Feb 2005
Location: LSGY
Posts: 4,333
Default 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.

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.
__________________
Mickey Coggins
http://rv8.ch
"Hello, world!"
Reply With Quote
  #4  
Old 03-11-2020, 05:09 PM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 3,276
Default

Or - use my static test rig and add a vacuum gauge, like this: https://www.amazon.com/HFS-Utility-V...3964448&sr=8-3

Carl
Reply With Quote
  #5  
Old 03-11-2020, 05:26 PM
barryrv10 barryrv10 is offline
 
Join Date: Dec 2007
Location: Fl
Posts: 175
Default

Hey Carl, where did you find the suction cup to go over the static port? Thanks much
Reply With Quote
  #6  
Old 03-11-2020, 05:35 PM
rocketbob's Avatar
rocketbob rocketbob is offline
 
Join Date: Jun 2006
Location: 8I3
Posts: 3,769
Default

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.
__________________

Please don't PM me! Email only!

Bob Japundza CFI A&PIA
N9187P PA-24-260B Comanche, flying
N678X F1 Rocket, under const.
N244BJ RV-6 "victim of SNF tornado" 1200+ hrs, rebuilding
N8155F C150 flying
N7925P PA-24-250 Comanche, restoring
Not a thing I own is stock.
Reply With Quote
  #7  
Old 03-11-2020, 08:48 PM
RVDan RVDan is offline
 
Join Date: Jun 2012
Location: Frederick, MD
Posts: 942
Default

Quote:
Originally Posted by rv8ch View Post
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.

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.
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.
__________________
Dan Morris
Frederick, MD
PA28-140
Hph 304CZ
RV6 built and sold
N199EC RV6A flying
Retired Aerospace Engineer and A&P/IA
Reply With Quote
  #8  
Old 03-13-2020, 05:50 PM
cdeerinck's Avatar
cdeerinck cdeerinck is offline
 
Join Date: Mar 2014
Location: San Marcos, CA
Posts: 418
Default Digital

Here is a cheap digital manometer: https://www.amazon.com/Manometer-RIS...6ER1KJ6DBNGRHY
__________________
~Chuck

DG-800S Sailplane
QB RV-8 -- Working on final wiring and the engine
84CX Reserved
Reply With Quote
  #9  
Old 03-14-2020, 01:31 AM
rv8ch's Avatar
rv8ch rv8ch is offline
 
Join Date: Feb 2005
Location: LSGY
Posts: 4,333
Default manometer

Quote:
Originally Posted by cdeerinck View Post
That's a nice one, and just what I'm looking for but need a larger range. That one and most on Amazon/Ebay only go to 2 or 3 psi. To test the altimeter to 20'000 ft, it would need to go closer to 8 or 10 psi.

Looks like I'll use the local maintenance shop for this pitot/static test.
__________________
Mickey Coggins
http://rv8.ch
"Hello, world!"
Reply With Quote
  #10  
Old 03-15-2020, 08:36 AM
Thermos's Avatar
Thermos Thermos is offline
 
Join Date: Jan 2005
Location: KASH
Posts: 597
Default

Quote:
Originally Posted by barryrv10 View Post
Hey Carl, where did you find the suction cup to go over the static port? Thanks much
Was just looking for that myself, it's at Harbor Freight -

https://www.harborfreight.com/dual-c..._q=suction+cup

HTH

ds
__________________
Dave Setser
CFII/MEI
EAA Technical Counselor/Flight Advisor
RV-7 N701ED Flying!
Nashua, NH (KASH) / Plymouth, NH (1P1)
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 05:09 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.