john2236

Thanks for the explanation wolfiverjoe, I knew it had to be set up something like that, and breaking the lens in the situation you described for a plane's equipment I can see as being helpful in that type of situation to help equalize pressure more quickly in case of an emergency.

Thank you, the cracks isn't bad at all, and I'm okay with it, as long as the altimeter functions as it is supposed to, and it does. I'll definitely keep you in mind doing if it becomes a problem. Thanks again

Didn't mean completely sealed, but there has to be a part of the altimeter that is sealed so that the pressure within the sealed part is compared relative to outside atmospheric pressure, which in turn causes the needle to turn

Thank you, gowlerk. I didn't think that the lens was the pressure barrier, but wasn't 100% sure and tried to look up the company but wasn't having any luck. Thanks again!

I'm just finishing up my A license and starting to get my own equipment. I got an Altimaster 3 from someone I know, and had a hard landing. The glass has a small crack now. I'm wondering if a crack that allows there to be an equilibrium between the inside and outside of the altimeter would throw off the calibration? Also, where can I download a manual for it?