Altimeter ?

Tall aircraft ????

It shouldn't be showing zero. It is the general air pressure setting that is used by all aircraft so that every aircraft's height is being measured by the same respective setting, so aircraft are actually at the corresponding height. This is very vague and probably doesn't help you a great deal 😕 so I'm sure someone else will explain it better 😉

I think its set at sea level(zero) So you are at an airport that is 700ft above sea level

There is a dial on the bottom of the alt which you turn to change the pressure setting. It is important to have this set correctly so the altimeter does not over or under read. Real world (UK) you will listen to the ATIS and get the barometric pressure reading "blah blah...QNH 1013" or in the US and on flight sim "altimeter 29.92". In this case the alt setting will need to be 29.92....if you fly using real world weather from high pressure to low pressure areas at a constant alt say 3000ft you would actually be flying lower when you fly into the low pressure area. Additionally you can leave your aircraft on a night with the alt reading "0" and in the morning it may read 30ft as the pressure has risen.....I will not delve deeper because I am sure you just want a simple answer!
Essentially the altimeter is a pressure instrument and you need to set the correct pressure setting for the days atmospheric pressure...isobars and all that! In your case wind it down to "0" and go fly.

The only time your altimeter should read zero is if you are at sea level. If your altimeter is reading 700 feet then the airport you are starting from is 700 feet above sea level or very close to it (depending on whether the altimeter has been adjusted for barometric pressure changes).

Bring up the map and check and see what the altitude is for the airport you are on, that is what your altimeter should read. You can get that information buy placing the mouse on the airport on the map.

Before I move away from the gate I press the "B" key on my keyboard like the prompt tells me to do. My altimeter then goes to the correct altitude according to the air pressure and the elivation that is that the airport at that particular time.

Regards,

Thanx for the answers.. Then i have learned something today to... thanx again..

just reset before flight no big hassle. i dont think...

earthqu8kes wrote:

just reset before flight no big hassle. i dont think...

If you are using real time weather it's a good idea if you are on a long flight to check in before landing and see what the weather is where you are, you may find there is a considerable change in the barometric pressure and your altimeter needs to be reset.

Or press "B" to correct it. 🙂

by reflex i do it every so often during flight. and i almost never forget b4 pushback.