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Topic: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-05 15:36:01 and read 24940 times.

I can't believe no one has commented on this yet...

Boeing's December 2012 airport planning guide update shows a 15,300 lb increase in OEW to 485,300 lb and a range with 467 pax and baggage reduced to just over 7500nm; and this is WITH the MTOW increase to 987,000 lb.

(remember we were told that 5000 lbs of weight was just removed this past year with 5000 more on the way for 2014)

Original OEW was to be 471,000 lb (and change), and was reduced in the Dec. 2011 planning guide to 470,000 lb.

(OEW for the -8f is increased by the same amount, with range dropping to ~4250 and payload to 292,000 lb at the 987k MTOW)

Something is VERY wrong here!

I will admit I am one of the biggest 747-8i fanboy's of them all, but if this is true, it destroys the business case for this aircraft.          

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: kanban
Posted 2013-02-05 15:39:41 and read 24927 times.

would you post a link to the source data please?

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-05 15:49:50 and read 24720 times.

here's the link: (Boeing commercial airplanes home)

http://www.boeing.com/commercial/airports/747.htm

click on the pdf's for 747-8 "description" and "performance" it's all there...

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Aesma
Posted 2013-02-05 15:57:37 and read 24602 times.

We're learning this now but it has been there all along (or current flying planes are even heavier), right ?

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-05 16:03:33 and read 24501 times.

That is what is so puzzling... Lufthansa says it is actually getting 1% better fuel burn than expected, given the GEnx-2b fuel consumption shortfall... what were they basing their expectations on in terms of OEW?

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Roseflyer
Posted 2013-02-05 16:09:00 and read 24385 times.

Quoting Aesma (Reply 3):
We're learning this now but it has been there all along (or current flying planes are even heavier), right ?

The airport planning guide is generic and does not reflect actual airline configurations. It's a good starting point, but it isn't exactly what the real numbers are. Weight and balance procedures are provided in FAA Advisory Circular (AC) 120-27. There's a weight and balance program for every airline based on their airplane configuration.

5,000lbs is a big deal as far as fuel burn goes, and this might help explain the popularity of the airplane, however comparing different models exclusively on the airport planning guide results in a lot of assumptions and inaccuracies that can skew the results. Airlines know this.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Stitch
Posted 2013-02-05 16:23:31 and read 24153 times.

In November 2006, Boeing gave an OEW of 212,000 kilograms | 466,700 pounds.

In January 2008, Boeing gave an OEW of 215,0000 kilograms | 472,900 pounds.

In January 2012, OEW was given as 213,000 kilograms | 470,000 pounds.

In December 2012, OEW was given as 220,128 kilograms | 485,300 pounds.

Range at MZFW in the January 2008 ACAP was 6250nm. This shrank to ~6000nm in the December 2011 and remains that in the December 2012 ACAP.

All figures are for a 467-passenger Boeing OEM configuration.

[Edited 2013-02-05 16:28:49]

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: sunrisevalley
Posted 2013-02-05 16:24:10 and read 24128 times.

Quoting Aesma (Reply 3):
We're learning this now but it has been there all along (or current flying planes are even heavier), right ?

Clearly some are just catching up , but there are others who have kept abreast of the topic.


Quoting SCAT15F (Reply 4):
what were they basing their expectations on in terms of OEW?

LH knew all along what they were getting, there would be no surprises. What Boeings guarantee to LH is and whether the aircraft meets it we will probably never know.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-05 19:23:39 and read 23231 times.

Quoting Stitch (Reply 6):

Thanks for that info Stitch-

I just don't get how the OEW can go down by almost 3000 pounds and then one year later -after a 5000 pound weight reduction- go up by over 15,000 pounds.

Also, going from 466,700 to 485,300 is just incredible, and rather disappointing.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: brons2
Posted 2013-02-05 19:48:36 and read 22902 times.

Quoting SCAT15F (Thread starter):
I will admit I am one of the biggest 747-8i fanboy's of them all, but if this is true, it destroys the business case for this aircraft.          

The 77W did that, but the 748 is not helping itself by being so porky.

The 777X will finish off the 748. That should be apparent by now.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Stitch
Posted 2013-02-05 19:49:02 and read 22900 times.

Quoting SCAT15F (Reply 8):
Also, going from 466,700 to 485,300 is just incredible, and rather disappointing.

Those earlier figures would have been projections since the 747-8 was still in the design stage.

The December 2012 figure could also represent the OEW of the first frames, which would have the full 10,000 pounds of overage. For a time, Boeing listed the 787-8 OEW based on the Block Point when it would be at spec weight. When that Block Point shifted to later frames, Boeing revised the OEW upwards to reflect the current Block Point OEW. So a "fully optimized" 747-8 might have an OEW of 475,000 pounds - close to the January 2008 OEW.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: kanban
Posted 2013-02-05 20:39:35 and read 21804 times.

One think to look is the purpose of the document... airport planning So it should show the maximums of the earliest members of the fleet since you never know which aircraft will arrive. Say you took the most recent and allowed no insurance then the heaviest arrived and sank through the asphalt...

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-05 21:04:45 and read 21310 times.

Quoting Stitch (Reply 10):

Thanks for that explanation, that makes a lot more sense. So for 2014 we have a 475,000 lb OEW with the GEnx-2b performing at or slightly better than spec, plus the trim drag reduction that comes with an activated tail fuel tank, and range might increase to 8100-8200 nm.

Of course Boeing still has room to increase MTOW as well, I would guess to at least 1,000,000 pounds based on testing to 1,010,000 pounds.

Either way, the 4% thrust bump for the freighter should become standard given that thrust has stayed the same from the start of the program (66,500 lb) while the aircraft was lengthened and MTOW rose from 960,000 lbs to 987,000 lbs.

Quoting kanban (Reply 11):

good point.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: PHX787
Posted 2013-02-05 22:47:37 and read 19639 times.

Ok so in layman's terms, what's going on here, the newer 748i models are going to have a shorter range because its heavier?

What's the point of that? It's like trying to sell a dead dog to a buyer intending on parading that dog at the dog show after the parade.

Quoting brons2 (Reply 9):
The 777X will finish off the 748. That should be apparent by now.

But isn't the 77X still just a hypothesis? I never saw anything at all regarding its production, unless you gentlemen can clue me in.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: aviaponcho
Posted 2013-02-06 00:12:11 and read 18320 times.

Quoting SCAT15F (Reply 4):

Hello
I think that LH means that it's 1% better than boeing revised specs that should include the real weights... Theses revised specs can be less than projected specs at the beginning of the program... (or the same if it's a well run program   )
Also, specs or garantees written in sales contract can be less than projected specs

That's what I understand

Thank you SCAT15F for the link and the news

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: seahawk
Posted 2013-02-06 00:23:41 and read 18124 times.

LH must have made s splendid deak with Boeing. LH seems happy with the 747-8 although all data shows that they should not be happy. I wonder how many performance clauses were not meht and how much discount LH could get becuase of that. I would not be surprised if they got those 747-8i for less money than they would have had to spent on a regular 77W order.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Pellegrine
Posted 2013-02-06 01:01:21 and read 17415 times.

Quoting Roseflyer (Reply 5):

The airport planning guide is generic and does not reflect actual airline configurations. It's a good starting point, but it isn't exactly what the real numbers are.

If anything, the (OEW) numbers in the ACAP are lighter and (other numbers/charts) more conservative than operator manuals.

Quoting Stitch (Reply 6):
All figures are for a 467-passenger Boeing OEM configuration.

Which operator has anything near a 467 passenger 3-class config? I get tired of these canned manufacturer numbers.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: rlwynn
Posted 2013-02-06 01:09:47 and read 17266 times.

How many routes for this plane are over 7500nm?

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: TC957
Posted 2013-02-06 02:17:55 and read 16164 times.

Wonder if this will influence CX's much-debated decision on a potential 748i / A380 VLA purchase since it looks like one key route like HKG - JFK won't be doable with a 748i now but should be with post-2015 A380's ??   

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: ferpe
Posted 2013-02-06 02:45:09 and read 15792 times.

Quoting TC957 (Reply 18):
it looks like one key route like HKG - JFK won't be doable with a 748i now but should be with post-2015 A380's

The A380 is further along in it's maturity, it started with the same problems as the 748, if you need the frame to fly very long legs in the near vicinity in time this can affect your decision, if it is a decision for the long term the frames true mature potential will decide. I expect the 748 to get back to spec 8000nm just like the A380 did (it has now passed it).

Another thing to have in mind is that the 748 spec pax count is done with an old spec seating standard, more so then the A380. If you load both to the same standard the 748 will have less seats and pax, ie it will be taking more fuel and flying longer. Say the diff is 40 seats, the seat+pax+bags weigh some 6t. Take it away with an average FF of 10.6t per hour this gives you an equalized 748 spec range of 8000nm, the same as the present A380 (the Dec 2012 ACAP spec range is ~ 7700nm not 7500).

I think you can say for equal maturity they have equal range if you seat the 748 and the A380 to the same standard.

[Edited 2013-02-06 02:48:06]

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: airbazar
Posted 2013-02-06 04:16:24 and read 14383 times.

Quoting ferpe (Reply 19):
The A380 is further along in it's maturity, it started with the same problems as the 748

The A380 was a brand new, clean sheet airplane. The 748i is a new version of a 40 year old airplane. The 748i is a far more mature platform than the A380 will ever be, IMO. So that excuse doesn't fly with me. The whole point of the 748i was that it was a very low risk and low cost (for Boeing), airplane. But if Boeing is having to give it away because it can't meet its contractual obligations (not a fact, just a plausible sugestion), then something would be seriously wrong.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: KC135TopBoom
Posted 2013-02-06 04:19:12 and read 14327 times.

Quoting TC957 (Reply 18):
Wonder if this will influence CX's much-debated decision on a potential 748i / A380 VLA purchase since it looks like one key route like HKG - JFK won't be doable with a 748i now but should be with post-2015 A380's ??

According to GCM, the HKG-JFK route is 7014 nm, well inside the B-747-8i range now.

Quoting ferpe (Reply 19):
The A380 is further along in it's maturity, it started with the same problems as the 748, if you need the frame to fly very long legs in the near vicinity in time this can affect your decision, if it is a decision for the long term the frames true mature potential will decide. I expect the 748 to get back to spec 8000nm just like the A380 did

  

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: sunrisevalley
Posted 2013-02-06 04:48:30 and read 13651 times.

Quoting TC957 (Reply 18):
one key route like HKG - JFK won't be doable with a 748i now but should be with post-2015 A380's ??
Quoting KC135TopBoom (Reply 21):
According to GCM, the HKG-JFK route is 7014 nm, well inside the B-747-8i range now.

JFK-HKG is a 16hr flight which gives it an ESAD of ~ 7500nm. The ZFW for this distance from the Dec.2012 load/range chart is ~265t. With OEW at ~220t this gives a 45t payload. or about max passenger load based on Boeings 3-class standard layout.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: airlinebuilder
Posted 2013-02-06 05:01:54 and read 13371 times.

I think we should all sign a paper of consent on DNR (do not resuscitate) so to speak, lets give the B748i a rest.....its one of those aircraft that has served its time. Lets just let her be the aircraft that could have and would have but did not really happen.......   

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: francoflier
Posted 2013-02-06 06:45:36 and read 11322 times.

Isn't the Tail Fuel Tank issue part of the range restriction, or has that been solved already?

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: sunrisevalley
Posted 2013-02-06 06:59:14 and read 11519 times.

Quoting francoflier (Reply 24):
Isn't the Tail Fuel Tank issue part of the range restriction, or has that been solved already?

In 2.0 airplane description in the ACAP sheets, the max fuel including tail tank is shown as 193.280t. On the load/range table it is shown as 191.656t. So it would appear that a range restriction is still in effect.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Stitch
Posted 2013-02-06 07:21:48 and read 11188 times.

Quoting seahawk (Reply 15):
I wonder how many performance clauses were not meht and how much discount LH could get becuase of that.

To the best of my knowledge, the 747-8 is meeting the contractual guarantees (which are written to be less then what the OEM expects the plane to be able to do).



Quoting Pellegrine (Reply 16):
Which operator has anything near a 467 passenger 3-class config? I get tired of these canned manufacturer numbers.

They have to put something in there.



Quoting francoflier (Reply 24):
Isn't the Tail Fuel Tank issue part of the range restriction, or has that been solved already?

It is and it has not.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Roseflyer
Posted 2013-02-06 09:10:45 and read 9060 times.

Quoting seahawk (Reply 15):
LH must have made s splendid deak with Boeing. LH seems happy with the 747-8 although all data shows that they should not be happy. I wonder how many performance clauses were not meht and how much discount LH could get becuase of that. I would not be surprised if they got those 747-8i for less money than they would have had to spent on a regular 77W order.

First off, Boeing and Airbus don’t make contractual guarantees at the actual projected performance of the airplane. They back off the numbers just in case. Early launch customers have the contractual guarantees backed off even further. As a concession, the manufacturer comes down on price for the early customers.

The 747-8 was launched in the conventional way. The airplane went through the gated design process and after Firm Concept the airplane was offered for orders. At Firm Concept they have a good expectation for what the target weight will be and what risks there are for it being higher. These are built in to the contractual guarantees with an additional buffer.

Late ordering customers almost always get an airplane that is better on paper than the early ordering customers. The consequence is that they have to pay a higher purchase price and they don’t get as desirable production slots.

To this date, I haven’t seen anything from LH or any other 747-8 customer that indicates the performance specifications have not been met. If anyone has this, I’d love to see it.
Just because they don’t meet what was initially anticipated in the media doesn’t mean it doesn’t meet the performance requirements.

Quoting PHX787 (Reply 13):
Ok so in layman's terms, what's going on here, the newer 748i models are going to have a shorter range because its heavier?

It’s just the airport planning guide being updated. I don’t think that the airplanes have suddenly gotten heavier. Boeing just finally updated the planning guide to show more realistic numbers.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: kanban
Posted 2013-02-06 10:35:19 and read 7351 times.

Quoting TC957 (Reply 18):
Wonder if this will influence CX's much-debated

Again no.. this is an Airport Planning Document.. not a sales brochure. It's intended audience is airport managers. It identifies the space requirements, maximum passengers that may load and unload, what the service requirements are and where they're located on the plane.. It tells the customer how big the hanger must be and what the maximum load on the floor/tarmac. It has zero to do with any contractual aspects of a sale.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: ferpe
Posted 2013-02-06 10:36:52 and read 7335 times.

Quoting Roseflyer (Reply 27):
Boeing just finally updated the planning guide to show more realistic numbers.

As they finally also did for the 788, I commend them for that. It is better to be straight and take the disappointment once, after that the discussion can focus on the virtues of the frame.

Airbus no longer publicize a spec OEW, to bad.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-06 11:19:02 and read 6538 times.

Wasn't the A388 overweight initially by a similar amount? something like 5-7 tonnes? I can't recall exactly.

I am also curious as to the oft-quoted sfc numbers by Lufthansa, which as I recall were something like 3.1 gal (or was it liters?) per passenger per mile for the A380 and 3.3 for the 748?

I wonder where those numbers stand now and where they will be once they get the "definitive" 748i of 2014 that has the pip, rear tankage activation for better cruise drag, and full 10,000 lb OEW decrease...

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: nomadd22
Posted 2013-02-06 11:34:37 and read 6223 times.

Wouldn't an airport planning guide be based on the heaviest of the line, or the first ones?

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Stitch
Posted 2013-02-06 11:37:08 and read 6269 times.

Quoting SCAT15F (Reply 30):
I am also curious as to the oft-quoted sfc numbers by Lufthansa, which as I recall were something like 3.1 gal (or was it liters?) per passenger per mile for the A380 and 3.3 for the 748?

I wonder where those numbers stand now and where they will be once they get the "definitive" 748i of 2014 that has the pip, rear tankage activation for better cruise drag, and full 10,000 lb OEW decrease...

That latest numbers I have seen LH publish (2011) showed:

A388: 3.4 liters per 100km 549 Seats
B748: 3.8 liters per 100km 362 Seats
A346: 4.1 liters per 100km 306 Seats
B744: 4.2 liters per 100km 344 Seats

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: lightsaber
Posted 2013-02-06 11:48:18 and read 6023 times.

Quoting nomadd22 (Reply 31):
Wouldn't an airport planning guide be based on the heaviest of the line, or the first ones?

Yes.  

I suspect these are better numbers to deal with:

Quoting Stitch (Reply 32):
A388: 3.4 liters per 100km 549 Seats
B748: 3.8 liters per 100km 362 Seats
A346: 4.1 liters per 100km 306 Seats
B744: 4.2 liters per 100km 344 Seats

That much more floor area and only 18 more seats... LH went premium with the 748I. It would look a little better with a cabin at the A388 density.

Lightsaber

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Roseflyer
Posted 2013-02-06 11:48:50 and read 6011 times.

Quoting Stitch (Reply 32):
That latest numbers I have seen LH publish (2011) showed:

A388: 3.4 liters per 100km 549 Seats
B748: 3.8 liters per 100km 362 Seats
A346: 4.1 liters per 100km 306 Seats
B744: 4.2 liters per 100km 344 Seats

Thanks for the number. Those are per seat figures if I remember right. That would definitely favor the A380. The A380 numbers are even better in the LH configuration since their configuration has a higher percentage of economy seats on the A380 than on other planes. LH has basically the same number of first and business class seats on the 747-8 as they do on the A380. They use all the extra cabin space on the A380 for economy seats, which makes a big difference when looking at fuel burn per seat or CASM.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: Stitch
Posted 2013-02-06 11:54:15 and read 5914 times.

Quoting lightsaber (Reply 33):
That much more floor area and only 18 more seats... LH went premium with the 748I. It would look a little better with a cabin at the A388 density.

Yes.

At 386 seats, it drops to 3.7 liters per 100km.

In 2009, LH was planning 405 seats and they projected a fuel burn of 3.5 liters per 100km.



Quoting Roseflyer (Reply 34):
Those are per seat figures if I remember right.

That is correct.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: ferpe
Posted 2013-02-06 13:33:04 and read 4259 times.

My model tracks both frames very well (within 50 nm on a trip of 7700nm), when I compare them on a kg/knm/m2 cabin I get 50.4 kg/knm/m2 for A380 and 52.5 kg/knm/m2 for the 748. That is a 4% difference, comparing the latest spec A380 (575t) with the 748 as given in the ACAP but with a cabin seating 427 pax (214t OEW for 748 and 275t for A380).

I would think the diff is in the order of less then 5%, it is such that if you can't fill the A380 you are better of with a 748.

The only real difference between the frames IMO is the still present halo effect of the A380, Emirates refer to it often as does other carriers. I haven't yet flown a A380 but flown the 747 zig times, to me the 748 is just another 747, i wouldn't change my travel plan to get on one, I will would for a A380 however if the trip is long.

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: aviaponcho
Posted 2013-02-06 13:48:08 and read 3974 times.

Ferpe, another difference is that the a380 is a 8500nm, and we know for sure that @575t it can do lax-dxb (or the other way)at full pax payload in a heavy emirates layout.
The 747-8 is only a 8000 nm bird. It mighy need another 10t mtow increase.
How much cargo can both take at 7000 nm

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: SCAT15F
Posted 2013-02-06 16:35:11 and read 2415 times.

Quoting ferpe (Reply 36):
My model tracks both frames very well (within 50 nm on a trip of 7700nm), when I compare them on a kg/knm/m2 cabin I get 50.4 kg/knm/m2 for A380 and 52.5 kg/knm/m2 for the 748. That is a 4% difference, comparing the latest spec A380 (575t) with the 748 as given in the ACAP but with a cabin seating 427 pax (214t OEW for 748 and 275t for A380).

Thanks Ferpe, that actually is much better than I thought. When you add the 2014 improvements such as the PIP, etc., the 748 actually becomes quite competitive.

Guess I got worked up for nothing!   

Topic: RE: Huge 748i OEW Increase: Range Reduced To ~7500nm
Username: sunrisevalley
Posted 2013-02-06 17:53:17 and read 2203 times.

Quoting aviaponcho (Reply 37):
How much cargo can both take at 7000 nm

That is more a function of the number of seats and thus the space left after loading the LD3's with the baggage. I am certain the A380 is volume limited with ~ 470-seats but the 748i is probably not assuming 400-seats. Both will haul about 16t less the spread between OEW and DOW .


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