Those who enjoy using real-world flight plans with RC3 might like to know that I've just released 115 plans for various types of Regional Jet aircraft in *.pln format. The plans cover a wide variety of UK internal and UK-Europe flights and are available from the libraries at AVSIM.com and Flightsim.com as 'rj_fpl.zip'.PeteP

thanks pete. i'll go grab them. you know how i love those wacky euro flights :-)

So you do, jd. Sorry, I should have sent you a gift-wrapped signed copy instead of making you go fetch your own! ;) Enjoy the flights but do watch those Transition Altitudes - some are as low as 3000ft! :-lol :-lol :-lol Pete

Pete putting the word "Altitudes" in bold made me think of an issue I've been meaning to ask.I understand the meaning of and difference between the terms "altitude" and "flight level", and for a long time I thought the difference between "transition altitude" and "transition level" were all a matter notation, i.e. 18000 feet = FL180.However, recently I have noticed that many of my Jeppesen SimCharts plates have both transition altitude and transition level printed on them, and they are different, sometimes by several thousand feet.How does one interpret and use this information? I know all about setting the standard pressure and that. It's the difference between the two concepts that I don't understand.

Henrik,If you want to know about the US system, I'll have to let Doug or Larry from the RC3 team explain it to you as their system is rather different from that used in the rest of the world. However, as your profile says you're Danish, you may be interested in what happens on this side of "the Pond". I'll use the UK as an example.As you've suggested, there is more than just "a matter of notation" between the two - they're actually very different things. The Transition Altitude is defined as the altitude at and below which vertical position is defined by reference to altitude (QNH). The Transition Level is officially defined as the lowest usable flight level above the Transition Altitude or, to put it in a more user-friendly way, the level at and above which vertical position is defined by reference to flight level (1013.2mB/hPa). The variable depth of airspace in between the Transition Altitude and the Transition Level is known as the Transition Layer. Put simply, the TA and TL mark the changeover points from QNH to standard setting (1013.3 mB/hPa) and vice versa.The essential difference between the Transition Altitude and the Transition Level is that the TA is a fixed and published value - the UK for example, has a standard TA of 3000ft with higher values at certain airfields - and the TL is a variable value which is calculated by ATC with reference to the current QNH. As the QNH changes, the TA remains the same but the TL changes. If you look at your Jepps for European airports you'll see a value stated for the TA - eg, Transition Altitude 6000ft, - but the Transition Level is given as "By ATC" because it has to be calculated. Here's an extract from the look-up table used by ATC in the UK to calculate the Transition Level with a constant Transition Altitude of 6000ft:QNH between 1050-1032 TL=FL55 QNH between 1031-1014 TL=FL60 QNH between 1013-996 TL=FL65QNH between 995-978 TL=FL70QNH between 977-960 TL=FL75QNH between 959-943 TL=FL80As you can see, the Transition Level can vary quite considerably as the pressure changes. The practical aspects of this for altimeter setting procedures within controlled airspace are as follows:When at an altitude below the TA and cleared to a flight level, set 1013.2 when leaving the altitude unless a vacating report at a higher altitude has been requested by ATC in which case set 1013.2 after passing this altitude. For example:1) at 3000ft and cleared to FL80, set 1013.2 when leaving 3000ft. 2) at 3000ft, cleared to FL80 to report passing 5000ft, set 1013.2 when passing 5000ft.It works in reverse in the descent when cleared from a level above the TL to an altitude:1) at FL100 and cleared to 6000ft, set QNH on leaving FL1002) at FL100 and cleared to 6000ft to report passing FL80, set QNH on passing FL80.In other words, when operating "on airways", it's not strictly necessary to know the TL because ATC will give a clearance in either altitude or FL format as approprite. However, when operating "off airways" this responsibility returns to the pilot and it becomes necessary to ask ATC for the appropriate TL.Hope this all makes sense.Pete

>Hope this all makes sense. It certainly does! I've it saved to my harddisk for future reference. Thank you very much. :-)