tockeyhockey
Posts: 880
Joined: Fri Feb 04, 2005 10:57 pm

Could The 747ADV Be A Twin?

Sat May 14, 2005 3:26 am

Let's say that the 747ADV uses a new, all-composite fuselage that allows it to drop an amount of weight proportional to change in weight when you compare the 767 to the 787.

Now, what if you strapped a couple of GE90s to the new, super light jumbo. Would the thrust be sufficient to turn the 747ADV into the worlds only jumbo-twin?
 
Glom
Posts: 2051
Joined: Sat Apr 23, 2005 2:38 am

RE: Could The 747ADV Be A Twin?

Sat May 14, 2005 4:05 am

The 747ADV wouldn't be a twin because it would change the 747 design too much, particularly all the stuff you propose. But any cleansheet 747 replacement will almost certainly be a twin. Slightly more powerful GE90s might indeed do the job if the aircraft in question was plastic.
 
aerlingus330
Posts: 812
Joined: Tue Nov 30, 2004 2:21 am

RE: Could The 747ADV Be A Twin?

Sat May 14, 2005 4:28 am

The GE90s has a Thrust Range of 75 000-127 000 pounds.
The Current member of the 747 Family has engines with 60 000 pounds of thrust. So, 60 000 X 4= 240 000 pounds of thrust.
Lets Take the Normal Thrust of the GE90s, which is around 110 000 pounds.
110 000 X 2 = 220 000.

Conclusion
If Boeing could get the Weight of the Boeing 747adv to below the weight of the current 747-400 then It may work. However, This would make the 747ADV severely underpowered and have no Back up in an emergency. The 747 Has no chance ever having 2 Engines. It would work, but it would be dangerous.

AerLingus330
Aer Lingus Airbus A330-300
 
411A
Posts: 1788
Joined: Mon Nov 12, 2001 10:34 am

RE: Could The 747ADV Be A Twin?

Sat May 14, 2005 11:55 am

IF the B747 was to be re-designed as a 'twin', the entire wing would need to be re-designed, due mainly to wing bending relief considerations...IE; additional weight outboard on the wing would not be sufficient, with only two engines.
Additional wing structure would be required...IE, much heavier.
 
User avatar
Starlionblue
Posts: 17212
Joined: Fri Feb 27, 2004 9:54 pm

RE: Could The 747ADV Be A Twin?

Sat May 14, 2005 2:52 pm

Quoting Aerlingus330 (Reply 2):
The GE90s has a Thrust Range of 75 000-127 000 pounds.
The Current member of the 747 Family has engines with 60 000 pounds of thrust. So, 60 000 X 4= 240 000 pounds of thrust.
Lets Take the Normal Thrust of the GE90s, which is around 110 000 pounds.
110 000 X 2 = 220 000.

Conclusion
If Boeing could get the Weight of the Boeing 747adv to below the weight of the current 747-400 then It may work. However, This would make the 747ADV severely underpowered and have no Back up in an emergency. The 747 Has no chance ever having 2 Engines. It would work, but it would be dangerous.


Sorry but your math is a bit off. If a quad has 4 x 60 000 lb of thrust, an equivalent twin would need 2 x 180 000 of thrust in order to ensure the same engine out performance. So you're way beyond "it would work". Apart from the fact that such engines are quite a bit beyond maximal current capabilities (a 50% increase in thrust, no less) I can hear the wings being ripped off right now  Wink


Also, while the GE90 may have benched over 120 000 lb, the highest thrust version in production delivers 115 000 lb. It's one thing to perform for a few hours in the test rig. It's another to deliver the same performance for years hanging under a wing.

[Edited 2005-05-14 07:57:20]

[Edited 2005-05-14 07:58:22]
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
tockeyhockey
Posts: 880
Joined: Fri Feb 04, 2005 10:57 pm

RE: Could The 747ADV Be A Twin?

Fri May 20, 2005 3:34 am

Quoting Aerlingus330 (Reply 2):
It would work, but it would be dangerous.

twins have, on average, a higher safety record than quads. boeing pushed really hard to make the 777 a twin, even though everyone at the time thought it was crazy. the 777 has been an astounding success. who is to say that boeing wouldn't push hard on the 747A?

twins are more efficient, require less maintenance, and are safer.
 
sanjet
Posts: 170
Joined: Fri Mar 25, 2005 1:58 am

RE: Could The 747ADV Be A Twin?

Fri May 20, 2005 3:51 am

Quoting Tockeyhockey (Reply 5):
twins are more efficient, require less maintenance, and are safer.

Don't want to sound to gritty but twins have a more stringent maintenance standard than quads to keep ETOPS certification. Although yes it might require less manhours total since you only have 2 engines, the work on a per engine basis would be higher on a twin.  bigthumbsup 
Will Fly For Food!
 
bhill
Posts: 1345
Joined: Thu Sep 13, 2001 8:28 am

RE: Could The 747ADV Be A Twin?

Fri May 20, 2005 10:30 am

Yup....411, I was gonna pose that posit...not just the "static" load on the wings but the moments of force at the mounting points...
Carpe Pices
 
CWUPilot
Posts: 122
Joined: Mon Mar 01, 2004 7:49 am

RE: Could The 747ADV Be A Twin?

Fri May 20, 2005 11:04 pm

True, it wouldn't work or get certified with 2 110,000 lb engines since single engine climb performance would be too low. But this is a good idea and Boeing will almost surely use a twin for its next "Jumbo Jet".

-CWUPilot
"The worst day of flying still beats the best day of real work."
 
Boeing Nut
Posts: 5078
Joined: Fri Feb 23, 2001 2:42 am

RE: Could The 747ADV Be A Twin?

Sat May 21, 2005 4:27 am

Um, I hate to break it to you guys, but this concept is already flying!


Modified Airliner Photos:
Click here for bigger photo!
Design © Robert Fall
Template © Daniel & Robert Fall



 duck 

 Big grin
I'm not a real aeronautical engineer, I just play one on Airliners.net.
 
User avatar
Starlionblue
Posts: 17212
Joined: Fri Feb 27, 2004 9:54 pm

RE: Could The 747ADV Be A Twin?

Sat May 21, 2005 6:57 am

Quoting Tockeyhockey (Reply 5):
twins have, on average, a higher safety record than quads.

I find that hard to believe. I think stats will show they are about as safe.

Quoting CWUPilot (Reply 8):
But this is a good idea and Boeing will almost surely use a twin for its next "Jumbo Jet".

Never say never but we're getting into diminishing returns on the R&D costs. Why develop a 180 000lb engine for a single aircraft? Sure, the GE90-115B is only for one aircraft, but it's not that far beyond other versions of the same engine. To ask for an extra 50% (which more or less demands a clean sheet design) when the number of airframes sold will be pretty low seems economically unwise.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
tockeyhockey
Posts: 880
Joined: Fri Feb 04, 2005 10:57 pm

RE: Could The 747ADV Be A Twin?

Tue May 24, 2005 2:55 am

Quoting Boeing Nut (Reply 9):
Um, I hate to break it to you guys, but this concept is already flying!

boeing nut, do you have any additional background on this? is this a real test for the future of the 747, or were they just testing the 777 wings?

any and all information would be greatly appreciated!!!
 
Boeing Nut
Posts: 5078
Joined: Fri Feb 23, 2001 2:42 am

RE: Could The 747ADV Be A Twin?

Tue May 24, 2005 3:13 am

Quoting Tockeyhockey (Reply 11):
boeing nut, do you have any additional background on this? is this a real test for the future of the 747, or were they just testing the 777 wings?

 bitelip 

Dude, that's a what I thought would be an obvious joke.
I'm not a real aeronautical engineer, I just play one on Airliners.net.
 
tockeyhockey
Posts: 880
Joined: Fri Feb 04, 2005 10:57 pm

RE: Could The 747ADV Be A Twin?

Tue May 24, 2005 4:39 am

so you're saying the photo was a fake? or is it a test of the 777 wing?

thanks for getting my hopes up. i'm excited about the prospects of seeing engines larger and more powerful than the ge90.
 
Boeing Nut
Posts: 5078
Joined: Fri Feb 23, 2001 2:42 am

RE: Could The 747ADV Be A Twin?

Tue May 24, 2005 5:15 am

Yes, it's a fake. Click on it and you'll find a lot more. Some are rather hysterical.
I'm not a real aeronautical engineer, I just play one on Airliners.net.
 
UAL747
Posts: 6725
Joined: Mon Dec 13, 1999 5:42 am

RE: Could The 747ADV Be A Twin?

Wed May 25, 2005 4:06 am

Obviously the pic is a fake, but whoever did it, did a great job. Almost looks believable, if you didn't know much about aviation!

UAL
"Bangkok Tower, United 890 Heavy. Bangkok Tower, United 890 Heavy.....Okay, fine, we'll just turn 190 and Visual Our Way
 
September11
Posts: 3293
Joined: Fri May 21, 2004 12:49 am

RE: Could The 747ADV Be A Twin?

Wed May 25, 2005 4:29 am

Quoting UAL747 (Reply 15):
Obviously the pic is a fake, but whoever did it, did a great job. Almost looks believable, if you didn't know much about aviation!

you got that right!!
Airliners.net of the Future
 
GQfluffy
Posts: 3072
Joined: Tue Apr 19, 2005 1:25 pm

RE: Could The 747ADV Be A Twin?

Wed May 25, 2005 8:05 am

Quoting Tockeyhockey (Reply 5):
twins have, on average, a higher safety record than quads.

LOL  rotfl  Um, you do realize that quads have been around for 50 years, while twins about half that. It's like comparing apples and oranges...


Like others have said... If you turn the 747adv into a twin, you're talking about $$$ being sunk into a new wing and other fuselage changes, not to mention waiting at least a year for engines to be built, and tested. That alone would kill the twin 747adv. At that point...why even bother calling it a 747? Just start with a new design. Easier and cheaper in the long run. If I'm reading what I've seen about the 747adv correctly, its a simple stretch, with new technology, wing improvements, and new engines.

LoL, you've also made my day with that 747 rewinged with 777 wings. HAHAHA! Don't take offense! It was just funnier then...well....alot of things...

fluffy
This isn't where I parked my car...
 
tockeyhockey
Posts: 880
Joined: Fri Feb 04, 2005 10:57 pm

RE: Could The 747ADV Be A Twin?

Thu May 26, 2005 3:02 am

i guess i'm the sucker of the day here at good old airliners.net.

at least give me this -- that is one hell of a good fake photo.
 
zvezda
Posts: 8891
Joined: Sat Aug 28, 2004 8:48 pm

RE: Could The 747ADV Be A Twin?

Tue May 31, 2005 2:02 am

Let's approach the original question a little bit differently. Given B787 composite technologies, could a B747-400 sized plane be designed to use two GE90s?

The GE90 has been tested at 127,000 lbs. of thrust and certified to 115,100 lbs. For the sake of argument, let's assume at it can be certified to 120,000 lbs. at a reasonable cost.

The B777-300ER has an OEW of 370,000 lbs and a MTOW of 775,000 lbs. The B747-400 has an OEW of about 395,000 lbs and a MTOW of 875,000 lbs.

Could a new design twin with 120,000 lb engines perform all the missions of a B747-400? The assumed increase in thrust would mean that our twin could have a MTOW of 810,000 lbs. The switch to composite construction would probably yield an OEW of about 350,000 lbs. With a max structural payload of 154,000 lbs (same as B777-300ER and slightly higher than the B747-400), 400,000 lbs of fuel could be carried (more than either the B777-300ER or B747-400).

So, yes, an all-new twin the size of the B747-400 could almost certainly be built using GE-90s. Of course, it wouldn't be a B747.

[Edited 2005-05-30 19:24:46]
 
ZRH
Posts: 4371
Joined: Tue Nov 16, 1999 11:32 pm

RE: Could The 747ADV Be A Twin?

Tue May 31, 2005 2:19 am

No. It would be an almost entirely new aircraft. They would not name it 747Adv but probably 797 an would cost a lot.

Who is online

Users browsing this forum: No registered users and 12 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos