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B738 climb fuel burn

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B738 climb fuel burn

Old 17th Jun 2022, 12:19
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B738 climb fuel burn

Hi folks, wonder if somebody can help me with some Boeing 737 performance calculations.

I need for a research project to show the total fuel use, broken down by segment of flight (take-off, climb, descent, landing) of a typical modern airliner. It doesn't matter very much what airliner, so long as it's something reasonably modern. However I've obtained a B738 performance manual - a type a few people here are familiar with I hope.

So I can see 25 lb/min taxi fuel use, 225 lb/hr APU use on the ground. That's easy.

I can see tables for take-off fuel as a function of brake release weight, airfield pressure altitude and end speed at 1500ft. All good there.

Loads of diagrams for fuel mileage in cruise as a function of speed, weight and altitude. That's straightforward too.

I can see data tables for approach idle fuel flow in lb/hr as a function of altitude and ISA deviation. Fine, presumably I just take data at the altitudes it's descending through and do a crude numerical integration.


However, I am completely defeated by fuel burn in the climb. I just can't seem to find the data / method in there for calculating fuel burn from end of the take-off segment at 1500ft, to start of the cruise segment at FL-whatever. The data must be buried in here somewhere, but I just can't find my way through the method.

Can anybody give me some advice on how to do these calcs?


(And incidentally, if anybody can point me at equivalent data I can access for any other modernish airliner, I should be in your debt for that as well).

G



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Old 17th Jun 2022, 14:15
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Here's a free 737-300 FPPM.

https://pdfcoffee.com/qdownload/flig...-pdf-free.html

Enroute Climb data is shown on pages 3.2.2 to 3.2.6

Enroute Climb
The Enroute Climb charts are based on 280/.74 climb
speed. Local ATC may require that 250 KIAS not be
exceeded below 10000 ft. See Flight Planning
Allowances in Chapter 2 for additional fuel burn when
this restriction is imposed.

Page 2.1.1
Climb
Trip Fuel and Time charts are based on 280/.74 climb
speed. Local ATC may require that 250 KIAS not be
exceeded below 10000 ft. Approximately 45 kg of
additional fuel is burned when this restriction is
imposed.
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Old 17th Jun 2022, 15:31
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Many thanks eckhard, that has some really useful performance charts in it and might just do the job.

G
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Old 17th Jun 2022, 17:26
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And it did, with a bit of extrapolation. Thanks again.

G

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Old 17th Jun 2022, 19:31
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Airbus FCOM PER-CLB

Climb tables are established at MAX CLIMB THRUST with air conditioning in normal mode and anti-ice OFF.
The climb speed profile is :
‐ 250 kt from 1 500 ft up to FL 100
‐ acceleration from 250 kt to 300 kt
‐ climb at 300 kt then M .78 up to selected altitude.
All charts are established with a center of gravity corresponding to 33 %.
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Old 17th Jun 2022, 19:36
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PM for detail, more where this came from. You need older editions as the fresh one have the section removed.
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Old 17th Jun 2022, 19:43
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This one has good educative potential, albeit limited to 500 NM. Note MLW = 66.000.



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Old 17th Jun 2022, 21:36
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You’re welcome! Glad to help. Sorry that it wasn’t a -800 manual. Maybe the -800 data is presented in a different way?
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