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Rook
28th Aug 2012, 03:14
What speed do you normally plan in your VNAV DES page? Do you keep ECON or change it?

misd-agin
29th Aug 2012, 02:52
Keep ECON? Rarely. If we're early and have a low cost index (CI) it will display 250 knots. That usually won't work into the high density cities we fly into.

.82/310 is a fairly typically combination. Behind schedule? .83-.84/320.

Chasing little airplanes. I usually program .80/300.

zlin77
29th Aug 2012, 12:39
Use Mach.83/310 Kts.....same as my two previous companies.

Wizofoz
29th Aug 2012, 19:18
We stick to ECON wherever possible.

Climb and descent are actually the phases that cost index has the most impact in terms of cost saving.

Sonny Hammond
30th Aug 2012, 06:04
True wiz but what about the fuel costs of half the traffic doing 310 and the other doing 250..? Like the good old days down south there should be a mandatory speed, say 280, good for turb, good for flow control and you won't get rocked to sleep enjoying he worlds slowest descent...

misd-agin
30th Aug 2012, 15:24
Climb and descent are the biggest factor in fuel savings? Playing with the FMC and changing the climb, cruise, or descent speeds showed changing cruise speed to have the largest impact on arrival fuel.

Flight duration might be a factor. The flights I checked were 3+ hrs long.