Contract Airline Services

"We are the protagonists of our stories called life, and there is no limit to how high we can fly."

Type rated on A330, B747-400, B747, B757, B767, B737, B727. International Airline Pilot / Author / Speaker. Dedicated to giving the gift of wings to anyone following their dreams. Supporting Aviation Safety through training, writing, and inspiration.

Tuesday, December 20, 2011

Tuesday Trivia

Altimeter errors are greatest when flying over mountainous terrain.

Why is this so?

Come back tonight to see the answer. (It's night already... answer below.)

Olympics from the space needle.

"What are those mountains doing in the clouds?"

For all those who commented, you will be entered into the contest to win a copy of Barry Schiff’s book, Test Pilot, 1001 Things You thought you Knew about Aviation.

Check out all the exciting prizes that will given away on the 22nd by clicking HERE. You still have time to enter.

Good luck!

Happy Holidays!

XOX Karlene


Answer: Wind flowing over and around mountains results in a venturi effect much like air flowing over a wing. This causes wind speed to increase and (static) pressure to decrease, which can cause indicated altitude to be significantly greater than true altitude.


  1. Mountain waves generally causes stronger winds which can cause local lowering of the pressure which creates an altimeter error. Also mountainous regions usually have colder surface temperatures than that closer to sea level, which can cause even more errors. I think I may have missed something with the height there.

    High to low, or hot to cold look out below.

    "what's that mountain goat doing way up here in a cloud bank?"

    (i cheated, but hey i'm refreshing on these things for two exams i have to write soon)

  2. Karlene, you really had to make me think about this one. My weather theory might be one of the more weak parts of my aviation knowledge. But I am thinking maybe that weather phenomenon associated with mountains like lenticular clouds and heavy mountain wave winds might affect altimeter readings. I haven't had the experience to know the real answer to this. Please post it when the drawing is done!

  3. Excellent Ramiel! Keep studying and you'll get all the answers.

  4. Daniel, not to worry on weather theory. That is a subject for an entire Masters program. Happy Holidays!!!

  5. I live & learn - thank you to all.


  6. Wow, I love these facts about things I'd never think about otherwise. Thanks!


Thank you for your comment! If your comment doesn't appear immediately, it will after I land. Enjoy the journey!