pressure test & dynon AOA

[prkaye]

To test my pitot system I was thinking of blowing air through a plastic tube into the pitot tube until the ASI reads some value, and then folding the plastic tube over and seeing if the ASI holds that value.
Questions:
1) how high should I make the ASI go when blowing into the tube, and how long should I expect it to hold pressure?
2) is it OK to tape over the Dynon AOA holes in their probe so as not to lose pressure through them?

[n468ac]

Originally Posted by prkaye

To test my pitot system I was thinking of blowing air through a plastic tube into the pitot tube until the ASI reads some value, and then folding the plastic tube over and seeing if the ASI holds that value.
Questions:
1) how high should I make the ASI go when blowing into the tube, and how long should I expect it to hold pressure?
2) is it OK to tape over the Dynon AOA holes in their probe so as not to lose pressure through them?

DO NOT BLOW INTO THE PITOT! Thats too much pressure.

[gasman]

Phil, Yes you can blow into the pitot tube without a problem, if you go easy......

Get enough clear tubing to go from the pitot tube, up to the seat so you can sit in front of the asi. Have a set of vice grips set and ready to clamp off the line when you are ready.

NOW...... go slow and blow into the tube. It will take about 13" wc (about .5 lb) to get the airspeed to read 140 knots or 160 stat. MPH. You will have a problem controlling the pressure, and it will jump all over. That's why I use a pressure bulb used on a blood pressure cuff with a bleed valve and a digital electronic manometer accurat to .05

BLOW EASY till you see about 200 whatever then clamp it off and wait. The asi will change with the change in tempture of the location. So if it is still holding about the same the next day at about the same temp......... THEN YOU HAVE A WINNER!!!!!

[D-Dubya]

The link below is another alternative. We've tried it and it works. With a little modification, you can check for leaks on both the static system and pitot system as well as verify calibration on your ASI.

http://www.iflyez.com/manometer.shtml

[n468ac]

Originally Posted by D-Dubya

The link below is another alternative. We've tried it and it works. With a little modification, you can check for leaks on both the static system and pitot system as well as verify calibration on your ASI.

http://www.iflyez.com/manometer.shtml

I've been searching for the link for him ... we used the same thing ... worked for us.

[Kevin Horton]

Pitot system leak check - Apply pressure to cause the ASI to indicate 150 knots (or the highest ASI reading, if less than 150 kt) and hold pressure. After 1 minute, leakage must not exceed 10 knots (from FAA AC 43.13-1B section 12-59). Release the pressure slowly to avoid damaging the ASI.

[Pilottonny]

No! This will not work on the Dynon Pitot! You would have to do it on the tube that is connected to the Pitot, because the pitot itselve leaks air (it is designed that way). I know because I asked Dynon whij I could hear the air whistle out of the pitot, when I blew into it (not connected to the instrument!).

Regards, Tonny.

[prkaye]

... from a previous post on another thread, this from "Dynonsupport" :

As a quick FYI, the heated pitot that we will be releasing shortly (I promise) will have leak holes that can be plugged to do checks more easily.

(I have the heated pitot). So it looks like I can safely just tape over those holes when I apply (gentle) pressure to the pitot tube.