Logan DeNelsky

At least I'm not crazy. Thanks guys! Logan

Hello All - I have been using FS9 for years and stubbornly resist switching to FSX. I have used many different addons at one point or another, most recently the PMDG 747. I have ruled out (hopefully!) any addons as the cause of my trouble. Lately, and I don't know why this hasn't become a problem at some other point, ATC has been advising me of an altitude deviation while enroute, usually in the 300-400 ft. range. Above 18,000 MSL the altimeter is set to 29.92 and the world of Flight Levels begins - and every time I have been dead on my flight level. However, if you bring up the information at the top (Shift-Z) the true altitude (MSL) is displayed, and that altitude is what ATC thinks I am at, despite the fact that my altimeter is set to 29.92 and I am flying the assigned flight level. Logically, this is only an issue when using real world weather, since when using the "standard" theme the altimeter setting is always 29.92, whether in the flight levels or not. Thus, there would never be any difference between one's true altitude and flight level - because of the standard pressure. I tested this on my other computer with a stock installation of FS9 and it holds true. So it isn't an addon that is messing it up. Try this: Default 737, standard weather - "clear skies" theme in FS9. Press Shift-Z until the true altitude is displayed. Whenever the altimeter setting is the standard pressure, your true altitude will equal your "flight level" because there literally is no difference - flight level is pressure altitude and with the altimeter at 29.92 that is EXACTLY what you are doing - flying pressure altitudes. Now, change to real world weather. I always do this through the default microsoft interface. Again, using the default 737, climb to FL250. Passing 18,000 MSL set the altimeter from the "local" setting to 29.92 - level off at FL250 and observe the difference between MSL (in red at the top of the screen) and the reading on your altimeter, which is set to 29.92. This is perfectly correct as it should be in the real world - you are now flying pressure altitudes. Now, for illustration purposes of my point, call up ATC and request flight following (obviously we should have been talking to ATC long ago if this one was going to be kosher - but you'll see where I'm going with this in a second). When ATC tells you "radar contact" and gives you your altitude, they'll say something along the lines of "United 123 radar contact 5 North of ABC, FL[xxx]." We are level at FL250, right? They should have read that back. Instead, they think you're at the MSL altitude, your "true" altitude. Thus, they think you are several hundred feet high/low the entire time. Puzzling, huh? Ideally I'd like to find a way to be able to download real world weather and leave the pressure changes out - so that I'm always at standard pressure, so that the true altitude and the FL always match up so my IFR doesn't continually get cancelled. Sorry for rambling. Any help would be greatly appreciated. Is there a setting in FSUIPC that can help with this? Logan DeNelsky Certified Flight Instructor Wadsworth, OH logandenelskycfi@gmail.com 0 Quote MultiQuote Edit