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B747 Double Full Deck... Why Not.?  
User currently offlineCun757 From Mexico, joined May 2004, 202 posts, RR: 0
Posted (8 years 10 months 2 weeks 14 hours ago) and read 8613 times:

I was thinking why Boeing never launch the 747 with full double deck, does any one knows...?


757 forever
35 replies: All unread, showing first 25:
 
User currently offlineTockeyhockey From United States of America, joined Feb 2005, 950 posts, RR: 0
Reply 1, posted (8 years 10 months 2 weeks 14 hours ago) and read 8590 times:

there are many factors, but i believe that the aerodynamics of the plane are perfectly suited to having the hump exactly the way it is on the 744. any further lengthening would create aerodynamic penalties that would make the jet inefficient.

furthermore, i don't believe the current engine system could support that much additional weight. a whole mess of re-engineering would have to take place to accomodate such a dramatic change. i think that if boeing wanted a true double decker, they'd be better served to start from scratch.


User currently offlineCun757 From Mexico, joined May 2004, 202 posts, RR: 0
Reply 2, posted (8 years 10 months 2 weeks 14 hours ago) and read 8554 times:

Quoting Tockeyhockey (Reply 1):
i think that if boeing wanted a true double decker, they'd be better served to start from scratch.

don't you think its cheaper and better to try with the one that all ready exist... I mean, change engines and work in the aerodynamics... And try to making work...?



757 forever
User currently offlineKiwiandrew From New Zealand, joined Jun 2005, 8548 posts, RR: 13
Reply 3, posted (8 years 10 months 2 weeks 14 hours ago) and read 8504 times:
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Hi Cun757

interesting idea - one potential problem I can see ( apart from redesign/aerodynamics etc etc which more competent people than me can comment on ) - most pax airlines earn a lot from belly hold cargo as well - if you had two full length pax decks but still the same amount of underfloor space for baggage and cargo then a lot of valuable cargo is going to be squeezed out by the increased baggage - I have been told ( by the usual friend of a friend , so not sure how accurate the info is ) that the cargo sales are often the difference between profit and loss on a given route - forgoing cargo revenue for more pax who are all chasing their way around the web looking for the lowest $$$ might not make economic sense .



Moderation in all things ... including moderation ;-)
User currently offlineA350 From Germany, joined Nov 2004, 1100 posts, RR: 22
Reply 4, posted (8 years 10 months 2 weeks 13 hours ago) and read 8405 times:

I have often been thinking the opposite: removing the top, make a new nose and maybe new wings and offer a stretched version. That would be a superb, light large a/c family and a good complement to the T7 family  stirthepot 

A350



Photography - the art of observing, not the art of arranging
User currently offlineCruzinAltitude From United States of America, joined May 2004, 415 posts, RR: 1
Reply 5, posted (8 years 10 months 2 weeks 13 hours ago) and read 8389 times:

Quoting A350 (Reply 4):
I have often been thinking the opposite: removing the top, make a new nose and maybe new wings and offer a stretched version. That would be a superb, light large a/c family and a good complement to the T7 family

A350

If Im not mistaken, doesn't that describe the A340, which has proven to be less than a good complement to the T7 family?


User currently offlineTockeyhockey From United States of America, joined Feb 2005, 950 posts, RR: 0
Reply 6, posted (8 years 10 months 2 weeks 10 hours ago) and read 8161 times:

Quoting Cun757 (Reply 2):
Quoting Tockeyhockey (Reply 1):
i think that if boeing wanted a true double decker, they'd be better served to start from scratch.

don't you think its cheaper and better to try with the one that all ready exist... I mean, change engines and work in the aerodynamics... And try to making work...?

i can't imagine boeing being able to simply "retro-fit" the 747 with a new, extended upper deck that ran the whole length of the airplane. this would require all new analysis of weight, construction, thrust, aerodynamics, electric systems, and on and on and on. a change of that magnitude would probably cost as much as a completely new airliner, in terms of production costs and changes to existing parts.

it would make more sense for boeing to start with a blank slate, incorporate all the knowledge they have gained from the 787 project in terms of bleedless engines and composite fuselages into a totally new design.

but, to be honest with you, it's simply not needed right now. airbus is going after the super-jumbo market, and boeing doesn't think that the super-jumbo market is large enough for one competitor, let alone two.

the 747adv is the right step, in my opinion. it is a simple stretch of an existing and very well proven design. it offers fleet commonality for many existing 747 operators, a lifting nose door option, and the ability to fly to all major airports without major infrastructure changes.


User currently offlineZvezda From Lithuania, joined Aug 2004, 10511 posts, RR: 64
Reply 7, posted (8 years 10 months 2 weeks 9 hours ago) and read 7992 times:

The B747-400 already stretched the upper deck as far as was reasonable to stretch it (for that length). Eventually, Boeing will start with a clean-sheet design and replace both the B777-300 and B747. I don't expect it to have passenger seating on the upper deck, though it may have passenger bunks, galleys, and lavs. Certainly it will have crew rest upstairs. The shortest version needs to have about the capacity of the B777-300 because it will be the next step up from the B787-10.

With 11 across seating on a single deck, a version with B777-300 floor area would be around 66 meters long. One can imagine 66, 73, and 80 meter long variants.


User currently offlineAirFrnt From United States of America, joined Jul 2004, 2825 posts, RR: 42
Reply 8, posted (8 years 10 months 2 weeks 9 hours ago) and read 7981 times:

It's simply a matter of capacity. You can bet that if there ever was that much demand for it (even during the regulation days) Boeing would have built it.

User currently offlineWdleiser From United States of America, joined Apr 2004, 961 posts, RR: 4
Reply 9, posted (8 years 10 months 2 weeks 8 hours ago) and read 7931 times:

Quoting AirFrnt (Reply 8):
It's simply a matter of capacity. You can bet that if there ever was that much demand for it (even during the regulation days) Boeing would have built it.

Boeing built the hump for the sole purpose of Cargo ops. So if Cargo shifted during flight it wouldnt go flying into the cockpit and the Hump also allows the liftable nose feature.


I just wish Boeing would do a comparison of the 744 with current engines and 744 with GenX engines. I just want to see the range and efficiency that engines alone would make.


User currently offlineBlueSky1976 From Poland, joined Jul 2004, 1874 posts, RR: 4
Reply 10, posted (8 years 10 months 2 weeks 8 hours ago) and read 7854 times:

Quoting A350 (Reply 4):
I have often been thinking the opposite: removing the top, make a new nose and maybe new wings and offer a stretched version. That would be a superb, light large a/c family and a good complement to the T7 family



Quoting CruzinAltitude (Reply 5):
If Im not mistaken, doesn't that describe the A340, which has proven to be less than a good complement to the T7 family?

Boeing already did that. Anybody remember Project 397 (or whatever that number was)? Four engines, circular fuselage, three aisles, I believe it had 2-3-3-2 cross section or something like that... plus 777-based supercritical wing... Base model had 450+ seats, the stretch would match A380-800 in capacity... too bad it was just a study...



STOP TERRORRUSSIA!!!
User currently offlineBoysteve From United Kingdom, joined Apr 2004, 937 posts, RR: 0
Reply 11, posted (8 years 10 months 2 weeks 8 hours ago) and read 7826 times:

Quoting A350 (Reply 4):
have often been thinking the opposite: removing the top, make a new nose and maybe new wings and offer a stretched version. That would be a superb, light large a/c family and a good complement to the T7 family

Are you describing the B773, afterall it can fit 386 pax into a 3 class formation according to this site


User currently offlineSlarty From Canada, joined Sep 2005, 342 posts, RR: 0
Reply 12, posted (8 years 10 months 2 weeks 8 hours ago) and read 7796 times:

Also, I read that the current 747 landing gear, tire/runway loading, wing support at mid-section, etc. is just about maxed out ... to substantially increase this would require a complete re-layout/design of the main load-bearing mid section.

User currently offlineLeezyjet From United Kingdom, joined Oct 2001, 4041 posts, RR: 53
Reply 13, posted (8 years 10 months 2 weeks 7 hours ago) and read 7735 times:

Don't forget that the Upper deck would be much narrower than the A380 too, and would only allow at most 3-3 seating with a single asile.

I guess it would look a little like this :-

http://www.cardatabase.net/modifieda...earch/photo_search.php?id=00000056

 Smile



"She Rolls, 45 knots, 90, 135, nose comes up to 20 degrees, she's airborne - She flies, Concorde Flies"
User currently offlineEMBQA From United States of America, joined Oct 2003, 9364 posts, RR: 11
Reply 14, posted (8 years 10 months 2 weeks 7 hours ago) and read 7723 times:

After much research in the late 1980's Boeing saw no market for the '747-500'. Right now it looks like Boeing was correct as sales figures for the A380 are yet to support that a market for such a jet exists.


"It's not the size of the dog in the fight, but the size of the fight in the dog"
User currently offlineAviatorTJ From United States of America, joined Jul 2003, 1838 posts, RR: 7
Reply 15, posted (8 years 10 months 2 weeks 7 hours ago) and read 7700 times:

The 747X would have brought it closer than it is now to a full double deck. I would love to see the mythical 747A come to look like the 747X-Stretch.



User currently offlineJetdeltamsy From United States of America, joined Nov 2000, 2987 posts, RR: 8
Reply 16, posted (8 years 10 months 2 weeks 7 hours ago) and read 7685 times:

While I've worked in this business for over 20 years, I don't claim to understand airline economics very well.

But it seems to me that a two deck 747 would dramatically reduce the space available for cargo. And with cargo, you make a lot more money per inch of space than you do in a passenger cabin.

I think it would make the aircraft unprofitable.



Tired of airline bankruptcies....EA/PA/TW and finally DL.
User currently offlineZippyjet From United States of America, joined Sep 2001, 5478 posts, RR: 12
Reply 17, posted (8 years 10 months 2 weeks 6 hours ago) and read 7598 times:



This is one of the reasons why a double decker 747 will probably remain a pipe dream. Many good points were brought up re: engine size and cargo capacity. You'd be literally designing a plane from the wheels up. And, the flying public likes New and Improved! Depending on how the A 380 does, could determine if Boeing would want to fly into the Uber Jumbo arena.
And by then, this design/concept could be resurrected or, Boeing may just design a BWB. And, from my understanding, the hump was an afterthought on the 747! Time will tell.







I'm Zippyjet & I approve of this message!
User currently offlinePITrules From United States of America, joined Jun 2000, 3150 posts, RR: 4
Reply 18, posted (8 years 10 months 2 weeks 2 hours ago) and read 7407 times:

The 747ADV will have an extended upper deck .

They will do this by using the existing space above the main deck as an area for passenger suites. Some system components will have to be relocated to accommodate this.

The upper deck will run almost the entire length of the main deck, WITHOUT extending the hump.



FLYi
User currently offlineSonic67 From United States of America, joined Jan 2005, 292 posts, RR: 0
Reply 19, posted (8 years 10 months 2 weeks 1 hour ago) and read 7315 times:

The original 747 design was a true double Decker but was changed to the current config half way through the design processes because of emergency exit concerns and stability issues. This change almost bankrupted Boeing at the time because they had to start over.

User currently offlineTockeyhockey From United States of America, joined Feb 2005, 950 posts, RR: 0
Reply 20, posted (8 years 10 months 1 week 6 days 17 hours ago) and read 5193 times:

Quoting PITrules (Reply 18):
The 747ADV will have an extended upper deck .

They will do this by using the existing space above the main deck as an area for passenger suites. Some system components will have to be relocated to accommodate this.

The upper deck will run almost the entire length of the main deck, WITHOUT extending the hump.

where did you get this information? has boeing made this public? not saying you're wrong, just that i have not heard this before.


User currently offlineMandala499 From Indonesia, joined Aug 2001, 6836 posts, RR: 75
Reply 21, posted (8 years 10 months 1 week 6 days 16 hours ago) and read 5035 times:

If I remember correctly, about 10 yrs ago, Boeing said that the 747 would need a new wing to support a full double decker... something they weren't willing to throw quarters into...

Mandala499



When losing situational awareness, pray Cumulus Granitus isn't nearby !
User currently offlineA342 From Germany, joined Jul 2005, 4681 posts, RR: 3
Reply 22, posted (8 years 10 months 1 week 6 days 15 hours ago) and read 4404 times:

Quoting Mandala499 (Reply 21):
If I remember correctly, about 10 yrs ago, Boeing said that the 747 would need a new wing to support a full double decker... something they weren't willing to throw quarters into...

Yes, the current wing wouldn´t support the weight.
If you stretch the upper deck you´ll add weight behind the wings. To get the balance work again, you would have to reposition the wing towards the back of the plane or stretch the fuselage in the front of the aircraft which would add even more weight.



Exceptions confirm the rule.
User currently offlineGeo772 From United Kingdom, joined Jul 2004, 519 posts, RR: 0
Reply 23, posted (8 years 10 months 1 week 6 days 15 hours ago) and read 4388 times:

Quoting Tockeyhockey (Reply 20):
where did you get this information? has boeing made this public? not saying you're wrong, just that i have not heard this before.

Was in Flight International a couple of years ago. The space behind the hump - roughly in line with the leading edge of the wing all the way back to between DR4 and 5. There is plenty of height available and with a redesign of the overhead bins along with rerouting of control cables, air conditioning ducting and some wiring looms quite a lot of space would become available. At the moment it is just a place to store a huge quantity of dust!

There wouldn't be the possibilty of windows in this area, although LCD bulkheads and projector systems could get round this.



Flown on A300B4/600,A319/20/21,A332/3,A343,B727,B732/3/4/5/6/7/8,B741/2/4,B752/3,B762/3,B772/3,DC10,L1011-200,VC10,MD80,
User currently offlineSolnabo From Sweden, joined Jan 2008, 851 posts, RR: 2
Reply 24, posted (8 years 10 months 1 week 6 days 15 hours ago) and read 4324 times:

The ADV gonna look like a stuffed turkey when full w/ pax. How much more can B do with the 747 model?  stirthepot 

Micke//SE  Confused



Airbus SAS - Love them both
25 Tockeyhockey : that's interesting. but if there is no way to have windows, how will they have escape doors?
26 Post contains images Kiwiandrew : my understanding is that pax would be in main cabin in normal seats for t/o and landing - and would move to the "private suites" for the cruise only
27 Post contains links Stitch : Correct. Airlines could put suites and even conference rooms in this space. It would also allow any lower-bay crew rest areas to be moved up, freeing
28 Tockeyhockey : that sounds like fun! imagine being able to have your own "room" on an airplane, with a bed, a tv, and maybe a mini-bar. if i were on one of those, i
29 Anxebla : Don't you think now is it too soon to speculate about it??
30 Post contains images Cun757 : That was exactly what I was thinking about it... I think in few years Boeing its going to give us a surprise with a new super jumbo, any way, Boeing
31 Ktachiya : I saw a special on NHK television about building the A380. I heard that they had many obstacles that they had to clear in order to make it a complete
32 ODwyerPW : I've lost my specs for the old proposed 747X-Stretch. How did it's fuselage length compare to what Boeing is proposing with the 747ADV Freighter? Of c
33 Cun757 : Yes, so now Boeing have the chance to think big... Remember 70 years ago the biggest plane was for 30 people... Can you imagine some one on this year
34 Post contains links and images GuamVICE :
35 Zvezda : No, I don't think it's too soon to speculate about it. Boeing's plan (which, like all plans, might change) is called Project Yellowstone. It consists
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