747-400 range question
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747-400 range question
ladies and gentlemen,
can someone please explain to me how carriers are able to operate the 744 (non extended range) on legs as long as VHHH-KORD which is over 7700nm?? i'm sure the high latutudes of the polar route help but isn't this range beyond the normal range of the aircraft?? are carriers weight-limiting them inorder to carry more fuel? any insight would be greatly appreciated.
kind regards,
can someone please explain to me how carriers are able to operate the 744 (non extended range) on legs as long as VHHH-KORD which is over 7700nm?? i'm sure the high latutudes of the polar route help but isn't this range beyond the normal range of the aircraft?? are carriers weight-limiting them inorder to carry more fuel? any insight would be greatly appreciated.
kind regards,
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Limited payload.
ELLX-PHNL 747-400F. Special charter flight (the 2 yachts for the Waterworld movie, Kevin Costner etc which were built in France) Aircraft was volumetrically full with about 25T payload. 7500NAM, reclearance (redispatch if you prefer), reserves were an interesting calculation. Max tanks fuel. Made a profit too.
Edit to say: I think it was BA that did EGLL-YSSY non-stop on a 400 pax to set a record. Unsure if they made any profit out of it.
ELLX-PHNL 747-400F. Special charter flight (the 2 yachts for the Waterworld movie, Kevin Costner etc which were built in France) Aircraft was volumetrically full with about 25T payload. 7500NAM, reclearance (redispatch if you prefer), reserves were an interesting calculation. Max tanks fuel. Made a profit too.
Edit to say: I think it was BA that did EGLL-YSSY non-stop on a 400 pax to set a record. Unsure if they made any profit out of it.
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You can read an article written by the record setting QF Captain here http://www.pprune.org/dg-p-reporting...nt-qantas.html
CR2
I don't think QF intended to make a profit on that flight, but they are KDFW-YBBN!
Anyway, how did you redispatch facing 2200nm of water? Was your redispatch point PANC?
GF
I don't think QF intended to make a profit on that flight, but they are KDFW-YBBN!
Anyway, how did you redispatch facing 2200nm of water? Was your redispatch point PANC?
GF
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slim75 - payload restriction.
Boeing performance charts -
http://www.boeing.com/commercial/air...s/7474sec3.pdf
Range goes over 8000 n.m. Chart doesn't show even lighter payload weights, which would allow even longer flights.
Boeing performance charts -
http://www.boeing.com/commercial/air...s/7474sec3.pdf
Range goes over 8000 n.m. Chart doesn't show even lighter payload weights, which would allow even longer flights.
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QF it is then. Thanks, I wasn't quite sure.
GF
That HNL flight was IIRC Nov 93, very shortly after CLX got its first 400Fs. I also remember it was -15C @ ELLX, so would assume we got a few more gallons in the tanks than usual. (I loaded that damned aircraft, nose and side doors open, howling wind to make life perfect. At 430am).
As Loadmaster I couldn't possibly discuss redispatch points. Other to say that they were long and involved
(As a matter of fact, I simply don't remember the WHERE).
I guess its correct to say that some aviation authorites have different criteria than others.
GF
That HNL flight was IIRC Nov 93, very shortly after CLX got its first 400Fs. I also remember it was -15C @ ELLX, so would assume we got a few more gallons in the tanks than usual. (I loaded that damned aircraft, nose and side doors open, howling wind to make life perfect. At 430am).
As Loadmaster I couldn't possibly discuss redispatch points. Other to say that they were long and involved
(As a matter of fact, I simply don't remember the WHERE).I guess its correct to say that some aviation authorites have different criteria than others.
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747 400 range question and BCF
thank you for the replies... and copy of the weight limitation and performance charts misd-agin... Thanks!! a follow on question if i may regarding the 747 400BCF.. a thread was started a few years ago regarding the external differences of the BCF from other 747 variants. but what about internal differences.? specifically, did boeing remove the HST system (horizontal stab fuel tanks) from the BCF or did the company leave them in? and does the 747 400F and 747 800F have HSTs?
kind regards,
kind regards,
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The BCF's, at least at my company, have had their horizontal stabilizer fuel tanks removed. The purpose built -400 freighters do not have horizontal stabilizer tanks. The -8 Freighter does not have horizontal stabilizer tanks either. The -8 Intercontinental appears to still have the stab tanks; like the -400, its listed fuel quantity is roughly 10,000 kilograms greater than the freighter's.
Granted I'm still an ultra neophyte to the world of 747's and freight, but, it's my understanding that zero fuel weight is the limiting number for the freighters on most missions. Filled to maximum zero fuel weight, the 747-400F can only take on roughly 100,000 kilograms of fuel, over 60,000 kilos shy of capacity even without horizontal stabilizer tanks. The number of missions in which the stabilizer fuel might be used apparently did not justify the cost of the equipment, not to mention the added maintenance. In addition the freighter is already considered "tail heavy" in regard to center of gravity....whether or not that factored into the design process I cannot say.
Granted I'm still an ultra neophyte to the world of 747's and freight, but, it's my understanding that zero fuel weight is the limiting number for the freighters on most missions. Filled to maximum zero fuel weight, the 747-400F can only take on roughly 100,000 kilograms of fuel, over 60,000 kilos shy of capacity even without horizontal stabilizer tanks. The number of missions in which the stabilizer fuel might be used apparently did not justify the cost of the equipment, not to mention the added maintenance. In addition the freighter is already considered "tail heavy" in regard to center of gravity....whether or not that factored into the design process I cannot say.
The Qantas flight from London to Sydney was an -ER version
misd-agin Reference the Dallas-Australia flights.
They will operate Sydney-Dallas-Brisbane-Sydney.
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747 400 range question and bcf
RandomPerson8008- thanks a bunch for the clarification and it makes alot of sense. i also understand that the ZFW is maximized with the freighter models which limit their range due to the priority of the carrier being the freight.
lastly, seeing as you fly the platform, have you noticed a change in epr when you set it on takeoff roll?? does it decrease/increase at all??
kind regards,
lastly, seeing as you fly the platform, have you noticed a change in epr when you set it on takeoff roll?? does it decrease/increase at all??
kind regards,
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RandomPerson8008- thanks a bunch for the clarification and it makes alot of sense. i also understand that the ZFW is maximized with the freighter models which limit their range due to the priority of the carrier being the freight.
lastly, seeing as you fly the platform, have you noticed a change in epr when you set it on takeoff roll?? does it decrease/increase at all??
lastly, seeing as you fly the platform, have you noticed a change in epr when you set it on takeoff roll?? does it decrease/increase at all??
Whether EPR indications on Pratt and Whitney and Rolls Royce engines remain constant during the takeoff roll I cannot say for certain because I have no experience with them. Logically the EPR should stay relatively constant once stabilized for takeoff, much like N1, and my differences manuals make scant mention of the subject.
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RB211-524s and PW4056/4062s
Assuming EECs are in normal mode and autothrottle is armed for departure, upon pressing a TOGA switch the autothrottle will set the FMC-selected reference thrust (ie the target takeoff EPR for RRs and PWs). This will be done by 65 kts, at which point the autothrottle servos will disconnect ("HOLD" mode) and provided neither pilot touches the throttles, the EECs will ensure that the EPR that was set remains constant. From our FCOM 1:
At 400' the autothrottle will re-engage ("THR REF" mode) and when the reference EPR changes (normally at thrust reduction altitude), the thrust levers will be moved accordingly. So in answer to your question, from setting takeoff thrust until at least 400' AAL when the A/T re-engages, the EPRs shouldn't change.
MD
PS Speaking of higher ZFWs on the freighters, on our 747-400ERFs normal MAXZFW is 277,144 kgs and can even go as high as 288,031 kgs albeit with a lowering of the MTOW...
When the engine is stabilized, EEC keeps thrust constant independent of outside air temperature and pressure.
MD
PS Speaking of higher ZFWs on the freighters, on our 747-400ERFs normal MAXZFW is 277,144 kgs and can even go as high as 288,031 kgs albeit with a lowering of the MTOW...
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EEC stands for Electronic Engine Control. It is similair to a FADEC, however less advanced in my opinion. The EEC provides overspeed protection, adjusts fuel flow to compensate for various atmospheric conditions, and provides thrust limiting. On the 747 each engine has one EEC which is powered by a dedicated electrical generator through the accessory gearbox.
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Qantas 744 clear-up
Just to clarify:
- the record flight from EGLL to YSSY was the delivery flight of Qantas's first 747-438, in 1989. It was not a 747-438ER (the first of which was delivered in 2002), rather a 'normal' -400 and had delivered across from Seattle before being filled with special fuel for the record flight;
- Qantas has not yet started operating its own equipment to KDFW, hence current schedules KDFW-YBBN would show a stop (transfer) in KLAX;
- Qantas will shortly be operating its own equipment (747-438ER) from Australia to DFW and back, running YSSY-KDFW-YBBN-YSSY, the BNE stop being required on the way back as the aircraft can't reliably fly KDFW-YSSY all year with revenue payload.
Anorak mode OFF...
- the record flight from EGLL to YSSY was the delivery flight of Qantas's first 747-438, in 1989. It was not a 747-438ER (the first of which was delivered in 2002), rather a 'normal' -400 and had delivered across from Seattle before being filled with special fuel for the record flight;
- Qantas has not yet started operating its own equipment to KDFW, hence current schedules KDFW-YBBN would show a stop (transfer) in KLAX;
- Qantas will shortly be operating its own equipment (747-438ER) from Australia to DFW and back, running YSSY-KDFW-YBBN-YSSY, the BNE stop being required on the way back as the aircraft can't reliably fly KDFW-YSSY all year with revenue payload.
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EEC
any chance you can clarify for me what EEC stands for??
MD