Results 1 to 5 of 5

Thread: Altimeter not reading correctly

  1. #1

    Altimeter not reading correctly

    I went flying in my 2008 Eurostar and all was fine. The following week (2nd march) I turned up at the airfield and could not reset the Altimeter to either read QFE or QNH. when I reset to the correct millibar for the airfield it was indicating the wrong height. e.g. 1019.0 should have read 398 feet QNH but was showing something like 700 feet

    I tried twiddling the knob today again and still I cannot set it to QFE or QNH.

    Any ideas on how to reset and or how to test?

    I did take the eurostar up with two gps ( so had two height readings) apart from the the altimeter not reading the correct height, the altimeter did move up and down in synch with the two gps

    In desparation


  2. #2
    Banned Banned500 Club
    Join Date
    Oct 2005
    A Lancashire lass settled in Essex

    Altimeter not reading correctly

    It depends on the altimeter. I can't remember the details but there should be a small scew near the pressure-setting adjustment knob. If you loosen this off you should be able to pull out the knob slightly and change the pressure setting without changing the displayed altitude (or vice versa, I said I couldn't recall the detail). You then push the knob back in and tighten the screw (boys, calm down!).

    Two potential problems that I'm aware of:
    1) it's a Chinese copy atimeter and the screw is just for show
    2) your altimeter has developed a slow leak in its bellows and you'll never get a stable reading (IIRC it actually becomes temperature sensitive).

    In either of those cases you are after a new altimeter, or ignore the pressure readings and just do your adjustments based on the displayed altitude and known airfield height.

    PS. This thread may help

    Edit: PS added

  3. #3

    Altimeter not reading correctly


    Many thanks, I will give it s go when i am back at the filed this weekend.



  4. #4
    Diamond geezer 500 Club
    Join Date
    Dec 2005
    North Cheshire UK.

    Altimeter not reading correctly

    Adjusted mine with that method some years ago Wayne....been fine since.


  5. #5

    Altimeter not reading correctly

    Result. Thanks for the info. It looks like screw 2 was not locked in place so when I adjusted the knob it changed the settings. All is now locked in place.

    Many thanks for the advice.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts