Obesity Kills The Dream?

[Schorsch]

Ah, my first topic in the new forum. And right on the topic.

Boeing has a respectable tendency to share quite a lot of data with the general public. In case of the B787 weight and performance figures were available as early as 2005. Regular visitors at Boeing's website (like me) have now different versions of these documents.

From those we see:
B787-8 Sep. 2005 preliminary ACAP:
MTOW: 476klbs
OEW: 239.2klbs

B787-8 Nov. 2006 preliminary ACAP:
MTOW: 484klbs
OEW: not given, but assume MZFW - MPL: 240klbs

B787-8 Sep. 2007 preliminary ACAP (latest issue):
MTOW: 484klbs
OEW: 252.5klbs

From '05 projections to '07 projections (the weight is finally known when it is on the scale) the weight growth is 5.5%.
The B787-8 is heavier than the OEW given for a A330-200 (which is given with 234.5klbs), while I would rate the A330-200 OEW as being without cabin installation.

Now, does the B787-8 have a weight problem after all?

[GerryW]

Sssshhh Schorsch! Not so loud!

[Schorsch]

In a recent interview the "Flightblogger" talked the Übervater of all buyers of civil aircraft, Mr. Steven Udvar-Hazy.
Besides other interesting comments, he said about the B787:

“I think the Boeing engineering and product team is totally focused on the 787-8 and -9 and also getting the 747-8 intercontinental airplane into production and get it certified both the passenger and freighter. With the weight creep on the 787-9 there’s some real issues that have arisen, for example the landing gear, we have to have to be at a different landing gear configuration on the -10. The wing will have to be beefed up so your creating more weight, which means more thrust which then gets the situation into a regime with Rolls Royce and GE where the original GENx design and the Trent design for the 787 was not intended to be at those thrust levels as to what’s required at the -10. I think Boeing is carefully looking at the -10, but I think it’s slipped in terms of its priority.”

In plain language: the weight projections for the B787 originally left the window for a double stretch with somehow degraded performance but without major re-design. But with weight increase this windows is closed now, as re-design work of the wing and the landing seems necessary. That doesn't make the -10 an impossibility, but it means that more resources have to be invested and that Boeing cannot make any serious offer now.

[Dmmoore]

In a recent interview the "Flightblogger" talked the Übervater of all buyers of civil aircraft, Mr. Steven Udvar-Hazy.
Besides other interesting comments, he said about the B787:

In plain language: the weight projections for the B787 originally left the window for a double stretch with somehow degraded performance but without major re-design. But with weight increase this windows is closed now, as re-design work of the wing and the landing seems necessary. That doesn't make the -10 an impossibility, but it means that more resources have to be invested and that Boeing cannot make any serious offer now.

I'm trying to figure out if you have a point or are just publishing Boeings own (already published) admissions?

[Schorsch]

In a recent interview the "Flightblogger" talked the Übervater of all buyers of civil aircraft, Mr. Steven Udvar-Hazy.
Besides other interesting comments, he said about the B787:

In plain language: the weight projections for the B787 originally left the window for a double stretch with somehow degraded performance but without major re-design. But with weight increase this windows is closed now, as re-design work of the wing and the landing seems necessary. That doesn't make the -10 an impossibility, but it means that more resources have to be invested and that Boeing cannot make any serious offer now.

I'm trying to figure out if you have a point or are just publishing Boeings own (already published) admissions?

I am using published data of several points in time to show the weight increase. That Boeing doesn't launch a press conference and telling people about its weight increase is clear. When the OEW at design freeze is value a, it shouldn't be value a+5% at first flight.

I haven't heard anything about the B787-10 since month. At the moment it would be a very delicate moment anyways (if you cannot bring the basic version in the air, news on the doublestretch sound stupid). However, since launch and initial offerings the OEW has risen 6.6t. Now it is 6t over the OEW after design freeze. Considering similar problems for the B787-9, its OEW gets close to 130t.
Using the B787's wing area (which actually haven't been published yet) and typical wing loading for "other advanced twin jets" (namely the A330-200 WV052 and the A350-1000), the MTOW_max can be fixed to 240t. Now one can check if a B787-10 fits in-between. It would, but with significantly reduced range. And that's what nobody gonna buy.

[Dmmoore]

If you look carefully, Boeing isn't pushing the -10 at the moment for the reasons you have noted.
I think Boeing has published the numbers for all aircraft for which it has firm orders including the weight increase. However no company holds a press conference too announce bad news unless there is no alternative.

"We" found out about the A380's weight problems through insider leaks and at the time "WE" were customers. Boeing is hoping to reduce the weight increase to a more realistic number but can you point to any new aircraft type that did not experience a weight increase over its design proposal? Dash number variants don't count.

[Schorsch]

If you look carefully, Boeing isn't pushing the -10 at the moment for the reasons you have noted.
I think Boeing has published the numbers for all aircraft for which it has firm orders including the weight increase. However no company holds a press conference too announce bad news unless there is no alternative.

"We" found out about the A380's weight problems through insider leaks and at the time "WE" were customers. Boeing is hoping to reduce the weight increase to a more realistic number but can you point to any new aircraft type that did not experience a weight increase over its design proposal? Dash number variants don't count.

You are misunderstanding me. I don't want to show that I found the big lie within Boeing, I just want reason that a viable business plan communicated to the press for quite a long period of time (they talked about the -10 for quite a while) seems to be out of reach now. If a company (Boeing) offers another company (Emirates) aircraft valued at several billion USD, which they obviously cannot deliver for technical reasons, I think it is worth noting.
I further want to point out, that the weight increase is the reason and that this weight increase is potentially higher than can be anticipated for a new aircraft. As example: A380 has +2%, the B787 currently has +6%.

Your statement about the weight increase of the A380 is basically wrong. Which insider leaks? As far as I can remember the increased MTOW and weight issues were out the day it flew first time. Anyways, a modest weight increase is a normal occurring and normally some gains disappear.