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IAS variation

Karl Kistler

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Patron
RV12iS, today i did my 3rd flight. First two flights uneventful.
During a steady climb with steady attitude suddenly the IAS indication in the Dynon HDX and as well the Stby speed-indicator started to climb, the overspeed warning came on. At about 210 kts the speed rise stoped and started slowly to com back. It stoped and stayed at about 35kts until after landing.
Any idea?
 
a clogged pitot will cause an airspeed indicator to act like an altimeter. When you climb the airspeed goes up, when you descend, it goes down. That's the way it works on an analog airspeed indicator anyway. Seems reasonable that it would do the same thing to your Dynon.
 
Might have hit a bug on your climb out. I have had a Cherokee pitot ice over in level cruise once and my indicated airspeed went to zero, but changing altitude would have given me a false airspeed. I also had a bug set up shop in my Searey pitot tube While in the hangar. I had to abort the takeoff when the airspeed did not come alive. When the airplane talks to you it is best to listen!
 
a clogged pitot will cause an airspeed indicator to act like an altimeter. When you climb the airspeed goes up, when you descend, it goes down. That's the way it works on an analog airspeed indicator anyway. Seems reasonable that it would do the same thing to your Dynon.

Thank you Terry, found glogged pitot tube!
 
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