B757 descent data
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B757 descent data
Wondering if anybody has descent tables for B752. I am talking about those which are giving distance and minutes to go from certain flight levels. In my FCOM we only have one table for descent speed .78/290/250.
We are trying to make fuel and time comparison on different descent speeds for the B752. I already checked FCOM from 2 other companies plus internet without any luck. Maybe those tables don't exist ???
We are trying to make fuel and time comparison on different descent speeds for the B752. I already checked FCOM from 2 other companies plus internet without any luck. Maybe those tables don't exist ???
Join Date: Mar 2011
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Have you tried looking at idle descent?
A CDA type of descent has fuel savings. A constrained approach, use a top of descent at 400, then drive it down from 50, this keeps you set in the pattern, can be easily implemented, and saves more fuel...
A CDA type of descent has fuel savings. A constrained approach, use a top of descent at 400, then drive it down from 50, this keeps you set in the pattern, can be easily implemented, and saves more fuel...
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Goldbird, I looked through my generic Boeing documents (straight from Boeing, not specific to any airline) and the .78/290/250 chart is the only one I see. There is nothing in the Flight Planning and Performance Manual. I have the AFM for the particular series 757s that I was flying a couple of years back, and of course it has nothing, either, although I didn't expect it to since that data is not required for certification.
My experience working directly with Boeing (while on a minor management pedestal) was that they can produce a tailored output of that kind of data based on specific inputs. Sadly, they don't do that for anyone...only those folks who are making lease payments on one of their airplanes (and have paid for the service contract). Your company should be able to have that discussion with them, but you or your pilot group will not.
My experience working directly with Boeing (while on a minor management pedestal) was that they can produce a tailored output of that kind of data based on specific inputs. Sadly, they don't do that for anyone...only those folks who are making lease payments on one of their airplanes (and have paid for the service contract). Your company should be able to have that discussion with them, but you or your pilot group will not.
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Play with the Cost Index. The FMC will then change the ETA and arrival fuel. We are flying with a CI around 15 most of the time. ECON descent is commonly around 252 knots IAS. This is slow, but it brings the descent point further back from the destination or first constraint. Of course, there are occasions when the ECON descent is not practical.