Aircraft fuel efficiency
Thread Starter
Joined: Jun 2011
Posts: 9
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From: khazikstan
Aircraft fuel efficiency
Hi
Can someone please help me with the following.
I wish to calculate the fuel effeceincy for the aircraft below. I need to use the following parametres below.
A/C 747
FUEL BROUGHT FORWARD 5005 LITRES
FUEL BURN =1850 LITRES
PLANNED AIR TIME = 1.19
SPECIFIC GRAVITY = 0.80
ACTUAL ZERO WEIGHT = 212900
Can someone please help me with the following.
I wish to calculate the fuel effeceincy for the aircraft below. I need to use the following parametres below.
A/C 747
FUEL BROUGHT FORWARD 5005 LITRES
FUEL BURN =1850 LITRES
PLANNED AIR TIME = 1.19
SPECIFIC GRAVITY = 0.80
ACTUAL ZERO WEIGHT = 212900
Joined: Feb 1998
Aviation Qualifications: ATPL
Posts: 1,595
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From: Formerly of Nam
A 747 with a burn-off of only 1,480 kgs.
I'd say that was your typical burn at 390T getting to RNW 25R at LAX
after a gatehold, which is pretty efficient in my book as it usually took
2000+ kg without it.
You won't be able to go far on 4 odd tonnes of fuel though.
I'd say that was your typical burn at 390T getting to RNW 25R at LAX
after a gatehold, which is pretty efficient in my book as it usually took
2000+ kg without it.
You won't be able to go far on 4 odd tonnes of fuel though.
Joined: Feb 1998
Aviation Qualifications: ATPL
Posts: 1,595
Likes: 0
From: Formerly of Nam
Maybe, but you'd have to be empty, be towed to the runway,
retain F20 after TO, fly a close-in circuit at 1,000ft and leave
the gear late in order to make it with all 4 Pratts or GEs still
working at the end of an idle-reverse landing roll.
One could shut down say No 3 on reaching 1,000ft to save
fuel in that situation, but I think it'd be 3/5ths of 5/8ths of
stuff-all considering the remaining distance to fly.
Since its the TO f/flow that buggers one up, I'd stay V2+10
straight to 1,000ft, starting the turn to downwind as early as
possible to get those GNMs/1,000 up and running.
retain F20 after TO, fly a close-in circuit at 1,000ft and leave
the gear late in order to make it with all 4 Pratts or GEs still
working at the end of an idle-reverse landing roll.
One could shut down say No 3 on reaching 1,000ft to save
fuel in that situation, but I think it'd be 3/5ths of 5/8ths of
stuff-all considering the remaining distance to fly.
Since its the TO f/flow that buggers one up, I'd stay V2+10
straight to 1,000ft, starting the turn to downwind as early as
possible to get those GNMs/1,000 up and running.
Joined: Jul 2001
Posts: 1,611
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From: Gold Coast
Interesting thinking, but how about just taking off with no payload and very little fuel .... on only the inboard engines. Leave the flaps at 10° all the way around and just go to 20° for landing, leave the gear down, and that way the ADP's on #1 and #4 should cope.
Joined: Feb 1998
Aviation Qualifications: ATPL
Posts: 1,595
Likes: 0
From: Formerly of Nam
Yep good one - F10 would be less drag than F20, but I dunno
about the total burn from brakes release to 1,000ft being less
for 2 eng/gear down vs 4 eng/gear up.
One of us will have to jump in a sim.
about the total burn from brakes release to 1,000ft being less
for 2 eng/gear down vs 4 eng/gear up.
One of us will have to jump in a sim.
Joined: Jul 2001
Posts: 1,611
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From: Gold Coast
The problem is that your question doesn't make a lot of sense - You have given the fuel burn and the flight time, (one or the other impossible for the 747 unfortunately) so you can work out fuel Vs time yourself.
Thread Starter
Joined: Jun 2011
Posts: 9
Likes: 0
From: khazikstan
Fuel efficiency
Hi
Thanks for getting back. I may have noted the figures below. This is the data I have that I am suppose to use. I may have noted the a/c type wrong. I have the values below for a few different a/c types flying to the same location.
FBF 7400
FUL 14365
UT LITRES
SG 0.787
FOD 18000
FOA 10400
PBO 6901
BLF 6.25
TF 6.32
LNT 7.55
BLN 8.05
PAT 1.22
ZFW 107254
Thanks for getting back. I may have noted the figures below. This is the data I have that I am suppose to use. I may have noted the a/c type wrong. I have the values below for a few different a/c types flying to the same location.
FBF 7400
FUL 14365
UT LITRES
SG 0.787
FOD 18000
FOA 10400
PBO 6901
BLF 6.25
TF 6.32
LNT 7.55
BLN 8.05
PAT 1.22
ZFW 107254
Thread Starter
Joined: Jun 2011
Posts: 9
Likes: 0
From: khazikstan
A/c effeciency
Hi
Thanks for getting back. I may have noted the figures below. This is the data I have that I am suppose to use. I may have noted the a/c type wrong. I have the values below for a few different a/c types flying to the same location.
FBF 7400
FUL 14365
UT LITRES
SG 0.787
FOD 18000
FOA 10400
PBO 6901
BLF 6.25
TF 6.32
LNT 7.55
BLN 8.05
PAT 1.22
ZFW 107254
Thanks for getting back. I may have noted the figures below. This is the data I have that I am suppose to use. I may have noted the a/c type wrong. I have the values below for a few different a/c types flying to the same location.
FBF 7400
FUL 14365
UT LITRES
SG 0.787
FOD 18000
FOA 10400
PBO 6901
BLF 6.25
TF 6.32
LNT 7.55
BLN 8.05
PAT 1.22
ZFW 107254
