malte
Well-Known Member
Hi Folks,
we all know that pitot-static testers are expensive pieces of test equipment. As explained in the "What did you do to save General Aviation" Thread, I am writing technical articles for AOPA Germany. In the issue 01/21, I discussed a pitot calibration and test tool with parts from "OBI Aerospace". (I guess you would call it "Lowe's aerospace" in america?)
Anyway, the article can be downloaded from here: https://aopa.de/wp-content/uploads/AOPA_Letter_01_2021.pdf (Page 8).
The working principle is quite easy: You use the mass of water to build a manometer with a u tube. This device does not need to be calibrated, as it uses physics only. (It is also described in the US Navy flight test engineering manual).
This is how such a tool can look like:
On the left I have mounted a PVC tube as the u-tube (drilled holes and fixated it with safety wire). The glass is a "water trap" for the use as static tester (coming up in AOPA 2/21). This is not needed for the pitot-testing function. The bulb is from a medical supply shop (blood pressure measurement supplies).
If the system is under pressure, you can read the height of the left and right arm of the manometer on the scale. If you need more contrast for a reading, add a bit coffee or tea to the water:
To make the system air tight, I use butyl sealing mass:
To evaluate the data, I have built a small excel-tool (attached).
I will update the thread, when I have written the static investigation article. Have fun testing!
we all know that pitot-static testers are expensive pieces of test equipment. As explained in the "What did you do to save General Aviation" Thread, I am writing technical articles for AOPA Germany. In the issue 01/21, I discussed a pitot calibration and test tool with parts from "OBI Aerospace". (I guess you would call it "Lowe's aerospace" in america?)
Anyway, the article can be downloaded from here: https://aopa.de/wp-content/uploads/AOPA_Letter_01_2021.pdf (Page 8).
The working principle is quite easy: You use the mass of water to build a manometer with a u tube. This device does not need to be calibrated, as it uses physics only. (It is also described in the US Navy flight test engineering manual).
This is how such a tool can look like:
On the left I have mounted a PVC tube as the u-tube (drilled holes and fixated it with safety wire). The glass is a "water trap" for the use as static tester (coming up in AOPA 2/21). This is not needed for the pitot-testing function. The bulb is from a medical supply shop (blood pressure measurement supplies).
If the system is under pressure, you can read the height of the left and right arm of the manometer on the scale. If you need more contrast for a reading, add a bit coffee or tea to the water:
To make the system air tight, I use butyl sealing mass:
To evaluate the data, I have built a small excel-tool (attached).
I will update the thread, when I have written the static investigation article. Have fun testing!