Testing AOA Probe

[Bud_Keil]

I have what I think is a defective Dynon AOA probe (P/N 100141-000, S/N 1452). The AOA function of my D10A EFS has never worked since I purchased the aircraft in 2013. During my last transponder test, the tech said I have a leak in my AOA circuit as he was not able to hold pressure. I have leak tested the entire circuit and believe I isolated it down to the probe. Removed from the aircraft, I blow into the AOA port and hear air rushing from the drain holes but nothing coming out of the AOA tube connection. Blowing into the pitot pressure port, air comes out of the pitot tube and no air leaking from the drain holes. Is this normal or a sign of a defective probe?

 

[rvator51]

I would double check for an obstruction in the AOA line like an insect which is caught in there. Can you apply air pressure to it to blow it out? Also run some kind of flexible rod/brush down it to try to dislodge whatever the obstruction is?

 

[Dynon]

There are built-in leaks on both the pitot and AOA ports, so if you were to blow into one of them and plug their respective lines, you would have air leak through their drains. BUT, if you aren't getting ANY flow from the AOA port when it's unrestricted, you might have a blockage in there. If that's the case, give our support team a call at 425-402-0433 so that they can help you troubleshoot further.