ebj1248650 From United States of America, joined Jun 2005, 1932 posts, RR: 2 Posted (3 years 6 months 2 weeks 5 days 3 hours ago) and read 10752 times:
At one time there was a suggestion the 737 replacement would likely be a scaled down 787. What happened to that idea? Was it unrealistic or has Boeing simply put it on the back burner until a more appropriate time?
Lufthansa From Christmas Island, joined May 1999, 3169 posts, RR: 10 Reply 2, posted (3 years 6 months 2 weeks 5 days 2 hours ago) and read 10559 times:
Using 787 technologies is one thing, but simply scaling down isn't going to work as they're designed for completely different missions for a start. One is going to need to be optimised for high cycles, fuel consumption consumption
during take off and climb will be more important then long range, its ability to be turned around in a certain time, to serve certain airport infrastructure, ratios of things like gallies to passengers (less needed on short haul etc), and even weight of the airframe per passenger as well as cargo ability. And this is goes on... in short, if they're going to be assigned for a completely different type of mission, they'll need to optimise the design for that kind of mission if they seriously wish to be effective. That.. and you simply couldn't scale down those powerplants to the appropriate size.
morrisond From Canada, joined Jan 2010, 224 posts, RR: 0 Reply 3, posted (3 years 6 months 2 weeks 5 days 2 hours ago) and read 10427 times:
However you could start with a 787. At least with the Aerodynamics, which they have some serious time into.
Where they can get some savings is by not reinventing the wheel. Cap the 737 replacement at 787 level of technology so you are not spending any resources developing new solutions. Use the same basic architecture, for structure/mechanical/electrical/avionics.
Still a ton of work, but with good computers, it's a lot easier to start with something you already have as you can just tell the computer to start with a 787 and shrink it x%. You now basically know how it will fly and can extrapolate a lot of the 787 performance data.
Just spend you development time and dollars on optimizing the 787 mini for the shorter range mission and spend the bulk of your time on figuring out how to crank out 300-400 CFRP frames per year in the most cost efficient manner.
The CFRP fuselage may not be any lighter, but supposedly cheaper to build, focus on that, cost.
If Boeing does a 737 Replacement now it won't have to last 35-40 years. A production span of 15 years would be more than enough to make a very nice profit as it should be easily over 5000 frames and get you to 2030 (assuming 2015-16 EIS of 787 mini) when you wlll have figured out how to profitably make an open rotor BWB replacement or some other much more efficient/exotic shape.
BMI727 From United States of America, joined Feb 2009, 15094 posts, RR: 26 Reply 4, posted (3 years 6 months 2 weeks 4 days 20 hours ago) and read 9935 times:
Quoting ebj1248650 (Thread starter): Was it unrealistic or has Boeing simply put it on the back burner until a more appropriate time?
It wasn't good enough. If you made a 737 sized plane with all of the technology of the 787, the gains in efficiency would not be large enough to be worthwhile, which is why Boeing has not launched the plane already. Furthermore, that is why Boeing is looking at a reengined 737 to fill the time gap between now and the time when they can build a 737 replacement with the necessary gains.
The bottom line is that the reason a 737 replacement has not been launched yet is not because Boeing doesn't want to, it is because the gains of such an aircraft would not justify the development costs. Whether or not the technology has reached the level necessary for a replacement to be viable is something we will probably find out pretty soon.
Why do Aerospace Engineering students have to turn things in on time?
This term has been used videly and as you say it is an oversimplification. But at some point after launching the 7E7 Boeing filed for a twin ailse 90-210 seat airplane patent. At that time some speculated that Boeing would keep the 7E7 cross section and shink it to a 737 replacement. There are probably others here who remember and has more information about that patent
Dream no small dream; it lacks magic. Dream large, then go make that dream real - Donald Douglas
BAW716 From United States of America, joined Nov 2003, 2018 posts, RR: 29 Reply 7, posted (3 years 6 months 2 weeks 4 days 16 hours ago) and read 8236 times:
No matter what design the 737 replacement will take, I'm sure it will be a "clean sheet" aircraft, taking the lessons learned from the 787 and applying them to the new bird. For sure a new wing, wider cabin and different engine will be part of the design, but apart from that, it's hard to know what the bird will do until Boeing does the analysis of what its customers are going to want from the 737 replacement.
Boeing does a pretty good job of listening to its customers before designing an aircraft, so as much as we (including myself) will like to speculate, we shall just have to wait and see information "leaks" out of Boeing about this new airplane. It'll be awhile though, since Airbus is going to have to do the same thing with the 320 (and they are not as far down the road with the 350 as Boeing is with the 787), so my gut tells me that Boeing will tackle the existing stuff first (get the 787 an a/w cert, start delivering airplanes) then get the 747-8 project finalized so it can sell some of the passenger planes (it needs to show better economics and comfort than the 380 to sell it) economics possible, but comfort is going to be tough, especially in cattle class....a 777 replacement (although I think the -200LR/300ER will be around for another 10 years or so), then a 737 replacement.
In other words, don't hold your breath for awhile.
David L. Lamb, fmr Area Mgr Alitalia SFO 1998-2002, fmr Regional Analyst SFO-UAL 1992-1998
dl767captain From United States of America, joined Mar 2007, 2539 posts, RR: 0 Reply 8, posted (3 years 6 months 2 weeks 4 days 13 hours ago) and read 6263 times:
It might not be a scaled down 787 but it will most likely resemble a smaller 787. The next 737 will use a lot of the 787 technology to make a composite frame and systems to become more efficient. I'm wondering if they will use a GTF engine for the replacement.