FishBike Posted August 4, 2014 Posted August 4, 2014 I've done a few flights lately that involved getting the Sabre up to fairly high altitudes (30,000+ feet) and have consistently run into what looks like a problem with the pitot/static system. Symptoms include: the airspeed indicator getting stuck at its current reading, the machmeter reading much higher than it should (Mach 1.2) and the vertical speed indicator getting stuck at zero. The altimeter still works fine, though. These problems go away after returning to lower altitudes for a while. I'd call it pitot icing except for a couple of things. I have pitot heat ON when this happens, and the vertical speed indicator shouldn't be affected by that. Any thoughts what this is? e.g. pilot error combined with a bug? Just pilot error? Just a bug? 1
Luzifer Posted August 4, 2014 Posted August 4, 2014 I had something similar descending from a high altitude, the airspeed indicator dropped until it was around 150 kts before it recovered as I leveled off. I was much faster. Effect like pitot icing but pitot heat was on. I think I was on idle during descent, but I think the windmilling kept the engine generator running. I've looked into some real world manuals, but I don't remember if pitot heat runs off the generator or battery DC. Maybe it was before I found out that I had to put the starter switch on "battery" after startup so maybe the pitot heat was realistically unpowered.
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