Pitot/AOA-Tube

[A321Flyer]

Hello

There are 2 small holes at the lower back end of the Dynon pitot/AOA-tube that seem to be connected to both pitot and AOA-opening of the tube?

If I blow into the pitot port and keep shut the tube, the air is leaking through one of these holes. Same for the AOA port.

How comes??? Is that for draining reasons?

Martin

 

[dynonsupport]

Both the Pitot and AOA port have internal drain holes. Those drain holes vent to the cavity, which is then vented to atmosphere via those drain holes. So what you are seeing is normal.

 

[A321Flyer]

Thank you for this information.

Am I right, that it is not possible to perform a "proper" leak test? I sealed both pressure lines (pitot, AOA) and both drain holes and put some air pressure on both pitot and AOA port. Result: very little air leaking through the holes of the mounting screws... (Gretz bracket)

Martin

 

[dynonsupport]

This is correct. You'll need to do the leak test upstream of our pitot.

 

[petehowell]

Hi Guys - I think the answer is here, but want to confirm my result was normal.

I hooked up the AOA pitot tonight and tried a leak check.  Pressure held great upstream of the pitot, but leaked when I had the test hose over the pitot opening and all the other holes covered with tape.  

Thanks,

Pete

 

[dynonsupport]

Yep, that's normal. Even if you cover all the holes you can find, you won't have a perfect seal.