I undestand what the cost index parameter is in the fmc, but was wondering if it is just "fluff" in the pic panel, or does it really feed performance parameters. I have used the standard 80, the leaner 79 and lower, and 81 and higher thinking it would be more aggressive less cost effective - but can't see differences in my flight specs, unless I am not looking at it the right way.Question 2, when I downloaded the latest airinc (is that the right name?) which was my first time doing so in 2 years, to upload my fmc info, I noticed that the amount of waypoints, and airport info increased as expected, but are you not only supposed to see airports that a 757/767 can suitably land at?? Sometimes there are so many airports on my HSI that it becomes a bit cluttered. Thanks for your time and insights,Neil

1) Cost index is not properly modelled in the current PIC. In the real world, a cost index will normally give you a variable cruise mach number - PIC gives you a constant mach number. However it still affects performance, in as much as the higher CI you enter the faster you will go and the more fuel you will burn. You're unlikely to see much, if any, difference between CI's of 79 and 81. You can enter anything between 0 and 1000 into les FMC, which in either extreme will give you cruise mach numbers of approx 0.78 and 0.82.2) Yes you should only be able to see 767 only fields but I guess the navdata guy Richard has enough on his plate without having to deal with this.It's 'AIRAC' btw.

That's a real good post cause i often wondered about that- being modelled and if it was at all.In real life West Jet use a cost index of 32 to 36. The pilots are on a performance bonus system -the more the airline makes the bigger their profit sharing cheques are, my kid says he flies with a lot of guys who are millionaires now and don't have to work at all if they don't want to but do for the love of it,so they take this cost index thing seriously. Louis

It's just an approximation in PICv1. The new PIC will properly model ECON speeds in climb/crz/descent, including proper calcs based on cost index and wind factors.Wade

Tom, Louis, and Wade,Thanks guys, I appreciate the feedback. Neil