Inadvertant flight into icing, pitot tube icing


I love flying!
Oct 17, 2015
Hello All,

Two weeks ago I inadvertently entered icing conditions in IMC. My pitot tube froze up and indicated airspeed dropped to zero. I turned on the pitot heat and the system restored itself after 10 seconds.

It was a short but scary encounter. I was straight and level at the time of incidence. Once the airspeed was zero the PFD displayed a right hand and decending turn while my head said that I am turning left. I immediately got a vertigo. SCARY.

What I would like to know:

1. Which aircraft instruments are affected by the loss of the pitot system?

2. Is there any backup like displaying GPS speed or else.

3. What are the warnings in the cockpit?

4. Where can I find it in the pilot manual?

My suggestion: there are four instances that I can think off where the airspeed suddenly drops to zero: pitot tube icing, corrupted pressure lines, pitot tube got clogged or the plane hits the ground.
That rapid airspeed change should be detectable by the software and give a "Turn on Pitot Heat" warning over the whole screen.
Who knows what could have happened if I didn't come up right away with the idea of turning on the pitot heat.   

Blue Skies



Dynon Staff
Staff member
Jan 14, 2013
Woodinville, WA
Glad to hear you made the right decisions after you experienced the icing event. Remember that our heated pitot (assuming it's ours) regulates its heat and doesn't just blast away, so do consider using it any time you're in IMC, regardless of whether you think you're going to see icing.

1. Airspeed directly. Attitude and a few other things indirectly. See the table in the pilot's user guide for some more details here.
2. Ground speed is always displayed on the PFD, but it won't be substituted on the IAS tape.
3. When IAS goes away, you'll see a GPS ASSIST message to let you know that attitude aiding is being assisted by GPS rather than by IAS.
4. The System Overview section has all of the above under the ADAHRS section.