Hello,Does someone know's which level system the Amerikans Using??Like us in Europe using the RVSM, North, Southbound RVSM and etc.Thanks,

Ramon,I think they just implemented RVSM. Do a search on All forums for RVSM. I read a thread the other day about it but can't remember which forum.Hope it helps,

Thanks Mats.

RVSM is in effect in the US as of Jan 20, 2005 for FL290 and above. Your aircraft must be equiped with RVSM compliant equipment. Odd altitude assignments are for magnetic courses 0-179 degress. Even alitidue assignments are for magnetic courses 180-359 degress. FYI: If your have RVSM compliant equipment then it is necessary to file with a /Q. If you don't have compliant equipment then you would continue to file with a /R.

Thanks allot George.I was always confused about the level system in the US because if you look at: http://www.cheaptickets.com/trs/cheapticke...alileo_home.xslAnd around 2000Z enter the flightnumber DLH456 you can monitor the flight from EDDF to KLAX and they mostly cruize at FL370 or FL390 but if you look at 0000Z for flight DLH457 you can see they also cruize at FL370 or FL390.

Check out the FAA RVSM ATC Manual at http://www.faa.gov/ats/ato/drvsm/docs/DRVS..._V2_17JAN05.pdfJerry PostKORF

>>FL390 but if you look at 0000Z for flight DLH457 you can>see they also cruize at FL370 or FL390.This is not mathematics. ATC folks can override altitude assignments if this is what they (or pilots) want to do.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2

The semi-circular rule is only a rule for VFR operations - IFR altitude assignments are per ATC. That said, the IFR crusing altitudes in the US are now 1000' apart between 290 and 410, so the rule may be broadly applied. The US has recently begun a transition to a navigational grid system to allow more direct routes between what are known as 'pitch' and 'catch' points, as well as easier parallel routing for multi-stream weather avoidance. The grid has been implemented in several centers, with more to follow.

I should clarify that the rule applies to VFR and IFR in uncontrolled airspace; IFR alt in controlled airspace is per ATC instruction. As indicated in the earlier note, the rule is usually applied when filing a flight plan, with the expectation that ATC may assign an altitude that is not what application of the rule would suggest.

In Canada RVSM went country wide on Jan 20th. Ofcourse, aircraft have to be RVSM compliant to be able to use it.