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Old 25th Jul 2004, 14:48
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BANANASBANANAS
 
Join Date: Jun 2001
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And one more question for you CJ, coming from someone who really should know the answer but I can't find it anywhere in my manuals. Does TCAS2 know the performance limits of the aeroplane it is fitted to or is it possible (for example) to get a climb RA that would take you above max certified altitude?

Thanks.

MikeMal, I think I can answer your question for you. If you are happy that you can follow a CLIMB RA in whatever engine configuration your aircraft is in, then there is a case for keeping RA selected. The big danger of course is that (as you do not know the required vert spd until the RA is commanded) if you are single engine (on a twin jet) and you are given an RA that you can't comply with because of reduced performance then the system falls down and a collision is more, rather than less, likely. Similarly, in a fully serviceable aircraft in a very busy TMA for eg (and particularly on parallel Rwy operations) it might be necessary (and at some airports I believe it is compulsory) to select TA only to avoid "nuisance" RAs. Hope this helps.
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