PPRuNe Forums - View Single Post - Why isn't "static" pressure speed-dependent?
Old 2nd May 2003, 22:19
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Genghis the Engineer
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That's a standard feature on single engine Cessnas - you smash the glass on the VSI since the instrument casing is connected to the static and it's an instrument that in extremis you can live without. You'd never do it in VMC, but if the static went in IMC and you need halfway reliable altitude readings for navigation / terrain avoidance, etc. it's a solution to the problem.

Piper, slightly more helpfully I feel, provide you with a small lever under the instrument panel that vents the static vent to the cabin.

It might put your readings 2-3 hundred feet / 10-20 knots out perhaps but that sort of error shouldn't kill you, whilst no meaningful altitude reading might.

G
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