B738 average burn
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Joined: Sep 2003
Aviation Qualifications: ATPL
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From: away from home
B738 average burn
I would like to ask any 737-800 guys out there what the average burn pr. hr. is on an average 3-4 hr. sector. I remember from my 737 classic days that is would burn 2,2-2,4 tons pr. hr.
tks.
o/c
tks.
o/c
Joined: Dec 2000
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From: very close to STN!!
from QRH
long range cruise control: p. PI.11.2
weight 65,000 kg FL 370 FF/ENG=1231 KG/HR
FL 350 FF/ENG=1218
FL 330 FF/ENG=1239
FL 310 FF/ENG=1252
so multipy by two (if both engs working)
another QRH chart gives:
air distance: let's use 1000 NM
FL 310=4600KG FL330=4400KG FL350=4300KG FL370=4200KG
for "shooting from the hip" estimates-some use 40KG minute for hold, some use 50kg minute.
another rough guide=200KG per hour each 1000 feet below flight plan level.
i am sure you will get quite a range of differences.
weight 65,000 kg FL 370 FF/ENG=1231 KG/HR
FL 350 FF/ENG=1218
FL 330 FF/ENG=1239
FL 310 FF/ENG=1252
so multipy by two (if both engs working)
another QRH chart gives:
air distance: let's use 1000 NM
FL 310=4600KG FL330=4400KG FL350=4300KG FL370=4200KG
for "shooting from the hip" estimates-some use 40KG minute for hold, some use 50kg minute.
another rough guide=200KG per hour each 1000 feet below flight plan level.
i am sure you will get quite a range of differences.
Last edited by stator vane; 10th September 2006 at 11:40.
Joined: Jan 2006
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From: In a far better place
Joined: Dec 2000
Posts: 523
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From: very close to STN!!
with winglets
Same Weight=65,000 KG LONG RANGE CRUISE
FL 370=1162
FL 350=1166 Kg/hr/eng
FL 330=1180
FL 290=1186
1000NM
FL 310=4900
FL 330=4700
FL 350=4600
FL 370=4500
did a double check for the 1000NM and that is what the book shows. fuel higher for the winglets but the times are shorter!
without winglets 1000 nm
FL 290=4700KG 2:45
FL 310=4600KG 2:42
FL 330=4400KG 2:37
FL 350=4300KG 2:32
with winglets 1000 nm
FL 290=5100KG 2:38
FL 310=4900KG 2:33
FL 330=4700KG 2:28
FL 350=4600KG 2:24
i must admit that i get bored very quickly doing these type of activities. perhaps later i will look into the subject further. but that is what the QRH book gives for the winglets and wingletless aircraft at ryanair.
anyhow, with a new flight crew notice that requires us to maintain at least a 1.45G manuever margin, we are always at least 2000 feet lower than usual. so the fuel savings forecast by the winglet sales department is seldom approached.
but regardless of fuel factors-- they do look good and we all know how important good looks are!
FL 370=1162
FL 350=1166 Kg/hr/eng
FL 330=1180
FL 290=1186
1000NM
FL 310=4900
FL 330=4700
FL 350=4600
FL 370=4500
did a double check for the 1000NM and that is what the book shows. fuel higher for the winglets but the times are shorter!
without winglets 1000 nm
FL 290=4700KG 2:45
FL 310=4600KG 2:42
FL 330=4400KG 2:37
FL 350=4300KG 2:32
with winglets 1000 nm
FL 290=5100KG 2:38
FL 310=4900KG 2:33
FL 330=4700KG 2:28
FL 350=4600KG 2:24
i must admit that i get bored very quickly doing these type of activities. perhaps later i will look into the subject further. but that is what the QRH book gives for the winglets and wingletless aircraft at ryanair.
anyhow, with a new flight crew notice that requires us to maintain at least a 1.45G manuever margin, we are always at least 2000 feet lower than usual. so the fuel savings forecast by the winglet sales department is seldom approached.
but regardless of fuel factors-- they do look good and we all know how important good looks are!
Last edited by stator vane; 10th September 2006 at 11:58.
