I was told a while back that the "Altimeter XXXX" at the end of some ATC communications was the controller letting you know the local altimeter reading at ground level.However, I often get comminications that are obviously not right. For Example, from a controller at a seaside airport (where the altitude should be very close to zero) something like "2992". In fact, I feel like I get 2992 very often.Is that a glitch? Am I missing something? Was I misinformed about the meaning of that phrase during ATC communication?Thanks.

This is likely to be dependent on what source you are using for weather, but I think what you are seeing may be gaps in weather reporting.If the simulator doesn't have a weather report for a particular area or airport, then it's likely to default to 29.92 or 1013. This typically happens at small, remote GA airfields since there will always be weather data for the major airports.Certain of the payware add-on weather generators have the ability to interpolate between weather reporting stations so that gaps don't appear, although this is more usually considered a problem if you end up with areas of default clear blue sky where there ought to be storm clouds! Whether that runs to providing guesstimated pressure readings I'm not certain.

The report you mention, gives the current air pressure at the airport. This varies with weather conditions, so does change. 2992 is usually what you get on fine days. This reading is used as a reference or calibration point for the altilmeter. so that you understand this correctly, this sets the airpressure at the airport not the altitude, when the altimeter is set with the correct air pressure it will indicate the correct altitude.

It is mostly dependent on what weather settings you have (i.e if you are using real world online updates), as most people have pointed out. It's also only of relevance if you are below transition altitude, which is where you change from being given 'altitudes' to instead being given 'flight levels'. FS is a bit crap in this respect, since it tends to use the global transition altitude of 18,000 feet, whereas the transition altitude can be much lower than that in many countries. So for the most part, to avoid ATC errors, you should stay on the local pressure setting below 18,000 feet, and switch to the standard barometric pressure setting of 29.92/1013.25 when you pass 18,000 feet.Somewhat annoyingly, there is no provision to enquire about the pressure setting in FS from the controller you are currently with, and whilst they do give you that info when you join the frequency, it is not updated to you if the pressure changes, so you either have to listen for another aircraft being told the setting when they come on frequency, or use an add that can update you with that info (this is one of the reasons why Flight Keeper is something I use, since it does do that, giving you a message across the top of the screen in FS when real world weather updates). that sort of thing is useful when FS ATC is descending you down for an approach and you get below 18,000 feet.Also worth noting (more out of interest than anything) is that FS does not tend to differentiate between QFE (Field Elevation) pressure readings and QNH (sea level) readings, instead simply saying 'altimeter' instead of 'QNH' or 'QFE', so it is somewhat simplified even in that respect. Real ATC transmissions generally tell you 'QNH 1015' or something of that nature. This is largely because most airliner FMCs use QNH as their baseline for the database of navigational stuff, and is something to watch out for when using VNAV in FS (as it is in real life).If you ever find yourself flying a real aircraft, you can have a good deal of fun with Q-codes. Most of them are somewhat antiquated these days, since they were really to make morse code transmission brief and easy to send, but it can be fun to ask an ATC controller one of the more obscure Q-codes and picture them scrambling for their book to find out what you asked. Try it on VATSIM if you are feeling evil. Here's a list of some of the obscure ones:http://www.kloth.net/radio/qcodes.phpAl