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four engines rather than twins

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four engines rather than twins

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Old 4th Jul 2011, 12:10
  #21 (permalink)  
 
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I remember when I was line training on the Electra as an FE. I asked my 'Old school' instructor if he wanted to fly the A300. His answer: I only fly a four engined aircraft cause they don't make one with five!
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Old 4th Jul 2011, 13:27
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Size matters!

Many companies choose 747s over 777 due to the size of cargo it can carry. 777s are able to carry (mostly) standard container size freight while 747s, with the added height in the main cabin and nose-door option on "true" freighters, can carry longer or higher freight and charge a premium to do it.
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Old 4th Jul 2011, 17:18
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Can't get my brain around -8 being more fuel efficient than 777.

If this was the case surely no-one would be ordering 777s - P nor F
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Old 4th Jul 2011, 17:29
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i'm sure the GEnx burns reasonably less fuel than the GE90-110, but four GEnx's vs. two GE90's? dunno .......
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Old 4th Jul 2011, 18:06
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Cause it makes no more sense than comparing it with the MD11. As for Thai and their relationship with Southern and the B777, I have no idea why Thai pulled out. I know why Air France tried to ditch theirs, and that was poor homework. What I do know is that FedEx cannot get enough of them, and that the experience AeroLogic has had with theirs was, at least partly, the reason why LH Cargo went and bought a few. I also know that the aircraft actually does more than the original brochure numbers, which is quite a surprise indeed. Later iterations have seen further improvements, and it is not unlikely we will see 108 tons payload in the future.
Why does a 777/MD11 make more sense? The MD11 doesn't have the capacity of the 777, and probably can't come close to the range of a 777 with a lighter load...

FedEx hauls mainly small packages, not heavy freight. AeroLogic does the same for DHL. I don't know what LH's plans are.

The package and freight markets are significantly different. As others have already pointed out, there is significant advantage with the 744F for heavy/outsize freight. The 744 can carry 108T HKG-ANC now, and lighter loads to 7600+ NM (e.g., 45T HKG-CVG).
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Old 4th Jul 2011, 19:18
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Why does a 777/MD11 make more sense? The MD11 doesn't have the capacity of the 777, and probably can't come close to the range of a 777 with a lighter load...

FedEx hauls mainly small packages, not heavy freight. AeroLogic does the same for DHL. I don't know what LH's plans are.

The package and freight markets are significantly different. As others have already pointed out, there is significant advantage with the 744F for heavy/outsize freight. The 744 can carry 108T HKG-ANC now, and lighter loads to 7600+ NM (e.g., 45T HKG-CVG).
Think you misunderstood me - my point is it doesn't make sense comparing the 777 with the MD11.

AeroLogic is flying for LH now on their week-end trunk routes to the US and Far East, and the aircraft seems to be doing the job they're asking of it.

As for the last bit, so can a 777F (if you consider 107.5 tons near enough). Except it would probably be able to haul closer to 55T HKG-CVG, and it wouldn't be fuel limited.

... and I'm still not convinced 4 x GENx will burn less than 2 x GE90. That would as good as make the 777F obsolete, whereas in reality it's selling pretty damn good.
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Old 4th Jul 2011, 19:53
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... and I'm still not convinced 4 x GENx will burn less than 2 x GE90. That would as good as make the 777F obsolete, whereas in reality it's selling pretty damn good.
In theory a quad will be more efficient in long haul operations since the engines can be sized for cruise rather than the engine failure/takeoff scenario. The A330/A340 and 777 have certainly muddied the case, but it is a mistake to assume that a twin is inherently more fuel efficient than a quad. It will be interesting to see what the final 747-8 numbers look like.

And it is also a mistake to seek a one airplane wins answer. Freight is complex, and different airplanes are going to be better fits for different routes, markets and operators. Some operators are clearly very happy with the 777, some appear to not be. And I work for one that took a very, very hard look at the 777F and then signed for the 747-8.
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Old 4th Jul 2011, 21:37
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... and I'm still not convinced 4 x GEnx will burn less than 2 x GE90. That would as good as make the 777F obsolete, whereas in reality it's selling pretty damn good.
Perhaps those GEnx's will burn more fuel, but what about the extra payload that a 74-8 will haul? Take a look at the big picture, not just the FF/Hr per engine.

Actually if you want to compare the 777F with anything, you'd be better off with a 747-400BCF. Both are able to lift around 107 tons, but the 777F can carry the load further. Given a similar load, say 75 tons, the B747-400F will burn 140ish tons on a specific Far East - Europe route. On the same route, on the same day, a B777F carrying the same 75 tons burned 100ish tons. And therein lies the reason why the B777F is the best thing since sliced bread in long-haul cargo, as long as you can live without a nose-door.
Comparing a 747-400 Boeing Converted Freighter with a 777F (factory build freighter) is comparing apples and oranges and a bit unrealistic IMHO. Of course the 777F will win, it will win hands down because the converted 744 will have a higher DOW and a lower MTOW compared to a factory build 744F.

Comparing a 744F with a 777F (both factory build full freighters) will give a far more reasonable, although still unbalanced, picture, with a 744F hauling a payload of roughly 90 tons and requiring a block fuel of 145 tons to SE Asia. Assuming the 75 tons load and 100t fuel for the 777F that comes down to ±1350 kg of fuel to carry 1 ton, versus the 744F's ±1600 kg fuel per ton payload. Granted, the 777 is a wonderful machine and at the moment has the better fuel consumption (not payload) than the 744F, but again let's be fair, the 777 is a much newer design with next generation engines, sleek wing, raked wingtips, FBW etc.

I'm curious to see how the 74-8 will perform versus the 777F. Will it be able to deliver larger 747 size loads with lean 777 style fuel flows? Will there be a market for these kind of loads? The future will tell...
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Old 5th Jul 2011, 04:28
  #29 (permalink)  
 
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T2E

On your example Europe to SE Asia. The 777F can haul max. payload (107.5) up to 10.5 hours of flight. You'll therefore find that the 777F is also able to haul 90 tons, and will burn around 105 tons getting it there. Makes the fuel burn per kg. of freigh carried even better than in your example.

Do agree, there's no single answer to what's best. But if you can live without a nose-door, the 777F will - at present - deliver the biggest bang for the buck.
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Old 5th Jul 2011, 05:57
  #30 (permalink)  
 
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As I read the above comments, twin v/s quad is still the same market wise. The 748 dominates in heavy lift and the 777f dominates in volume pound per mile value. Two different markets. None the less as for freight on long sectors, if it ain't Boeing it ain't going. For the freight market.
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Old 5th Jul 2011, 09:43
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SMT Member, thanks for your info! Spectacular numbers indeed for a twin!
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Old 6th Jul 2011, 10:32
  #32 (permalink)  
 
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What a splendid, thoughtful, polite and informative thread by all concerned. Well done chaps! Breath of fresh air so good for you!
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