Airspeed Anomaly

jvolkober

New Member
Joined
Apr 26, 2009
Messages
32
I am having difficulties with the airspeed indication on my SkyViiew system.  At this point this appears to be the situation:

When stationary applying pressure to the pitot tube, I get airspeed reading on the screen.

When under power, attempting initial flight, I do not get airspeed reading from the primary ADAHRS and intermittent and unreliable readings from the secondary ADAHRS.

I have inserted a mechanical, analog indictor mid-way between the pilot tube and the ADAHRS.  I appear to get an appropriate reading from both the Dynon system and the mechanical, analog unit when pressure is applied to the pitot tube.  However, under power on a high speed taxi, sufficient to take-off, I get a reading on the mechanical unit and none on the primary ADHARS and intermittent and unreliable readings from the secondary unit.

I am looking for suggestions for what to look at to resolve the problem of no or intermittent airspeed readings on the Dynon system.

Thank you for any assistance you can provide.

Additional question for Dynon Support: if I am getting compass, bank angle, temperature and likey altitude indications on the screen, is it still possible that the airspeed issue is due to a bad twisted pair connection or conversely, given that other indicators are working, the network connections are okay?

John Volkober
 

preid

Member
Joined
Jan 22, 2010
Messages
754
Location
SoCal
Have you done the ZERO pressure calibration yet?
Give it a try
SETUP MENU > HARDWARE CALIBRATION > ADAHRS CALIBRATION >
 

jvolkober

New Member
Joined
Apr 26, 2009
Messages
32
I did not see anything in the documentation regarding calibration of the airspeed indicator.


That said, after goring around the bush the long way many times, the issue finally boiled down to a faulty pnuematic connection causing a leak in the system. Our rough test of placing pressure on the pitot tube by gently blowing on it masked the leak; we were able to place sufficient pressure on the system to get an air speed reading overcomig the leak. Underway, however there apparently was insufficient pressure to register airpseed on the Dynon system up to abount 50 mph ground speed per the GPS. Simple issue that we missed early in the investigation causing many hours of testing the network circuit.
 
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