lately, went I fly above 210ft. And I meet my cursing atitude, with my altimeter set to the correct setting, ATC tell me that I'm not at my asign altitude.

That's because you have to set your altimiter to 29.92 above FL180

thank you, I try that.

jerrycwo4Once and for all, what is the answer to the almost same question, What if your flying right at 18000 feet. Does the change to 29.92 start at FL180, or ABOVE FL1800 i.e, 18,100 feet?jerry

It starts at the first flight level, FL180, i.e. an assigned altitude of 18000 feet.

I believe you're not allowed to fly at FL180 in real life.

"(...) my cursing atitude (...)"Such an attitude might get you fired from your airline (grin)!Jaap Verduijn.

Where did you get the idea that you cannot fly at FL180?When the altimeter setting goes below a fixed setting then FL180 becomes unusable because someone flying at 17,500 with a current altimeter setting, not 29.92 could result in less than 1,000 ft vertical seperation of traffic.i.e. If the current altimeter is 29.92 or higher than FL180 can be used.If altimeter setting is 29.91 to 29.42 then the lowest usable FL would be 185 (ATC would disregard this and not use anything lower than FL190)Setting 29.41 to 28.92 then lowest usable FL would be 190, 28.91 to 28.42 FL195 (sould use FL 200, ATC does not assign +500 ft. altitudes for IFR.28.41 to 27.92 FL 200

Of course, the transition altitude varies from country to country. FL60 is the 1st FL in UK I think. Should know this....damn! Failed my exams!Can you change the transition altitude in FS? I thought you could.

It's 3000ft in the UK - but each TMA have individual TA's just to confuse matters. Most are 6000ft - so you were correct.