Register

Your Altimeter Is Lying

All instruments in your panel lie some of the time. Some of them lie all the time. Even if you have a glass panel that eliminates things like compass turning errors, and its connected to an air-data computer so it always know the true airspeed, your back-up systems likely are steam gauges, the old-fashioned, mechanical kind. Thats the bad news.

Gemini Sparkle

Key Takeaways:

  • Altimeters measure pressure, not true altitude, and are calibrated to a standard atmosphere (ISA); real-world variations in pressure and temperature inherently cause indicated altitude to differ from true altitude.
  • Incorrect altimeter pressure settings or extreme low-pressure conditions can lead to an aircraft being significantly lower than indicated, posing a safety risk, with ATC providing guidance for extreme pressure scenarios.
  • Cold temperatures also cause altimeter errors, resulting in the aircraft flying lower than indicated, necessitating mandatory cold temperature corrections at specific airports and temperatures for safe operations.
See a mistake? Contact us.

All instruments in your panel lie some of the time. Some of them lie all the time. Even if you have a glass panel that eliminates things like compass turning errors, and it’s connected to an air-data computer so it always know the true airspeed, your back-up systems likely are steam gauges, the old-fashioned, mechanical kind. That’s the bad news.

Ready to Sell Your Aircraft?

List your airplane on AircraftForSale.com and reach qualified buyers.

List Your Aircraft
AircraftForSale Logo | FLYING Logo
Pilot in aircraft
Sign-up for newsletters & special offers!

Get the latest stories & special offers delivered directly to your inbox.

SUBSCRIBE