Hello!when reading USA/Canada flightplans, I'm often surprised by the number of "DCT" that are used, such as in this example:(...) 40N060W DCT DANER/M084F400 A699 BURTT DCT TROUT/N0482F390 AR5 CARPS A700 HOBEE DCT LAL DCT PIE. It is the final part of a BA EGKK-KTPA flightplan.I mean, I perfectly understand that a DCT routing is always the best option, fuel- and time-wise, but what I would like to ask is: where can I find a document (if any) that specifies the "DCT limits" for USA and Canadian airspace, just like we have in Europe (http://www.cfmu.eurocontrol.be/rad/2sep/dct.pdf)?That would be a great help in order to build realistic flightplans to/from the North American area.Thanks in advance! :-)

Hi Nicola,In the US they use a completely different system than in Europe, as you probably already knew. They don't have direct limits for specific areas, but limits regarding the maximum usable distance of navigational aids. You might want to read section 5-1-7 in the Aeronautical Information Manual (http://www.faa.gov/ATpubs/AIM/Chap5/aim0501.html#5-1-7; scroll down to d. Area Navigation (RNAV)), and section 4-1-1 of Order 7110.65P (http://www.faa.gov/ATpubs/ATC/Chp4/atc0401.html#4-1-1).Cheers,http://home.planet.nl/~duijn181/cu2/koen.jpg

Thanks Koen! I'll have a look at those documents and let you know if I get the picture or not ;)Cheers,