Boeing 787 Dreamliner - Mark Wagner [22]
The resulting matrix produced four main options: a baseline LR seating about 200 to 220 in three classes, with an 8,970-to-9,200-mile range; a stretched LR seating up to 260 with a range of up to 8,500 miles; a baseline SR seating 320 to 340 (in two classes), with a 3,450-to-3,900-mile range; and a stretched SR seating 280 to 310 with a range of up to 4,600 miles. Both baseline SR and LR aircraft had the same length, of about 190 feet, while the stretch was lengthened by almost 23 feet, to be some 213 feet long.
Despite this plethora of options, Boeing still drove to “keep things simple,” with as little variation as possible among the versions. Yet satisfying such divergent requirements at equal levels of efficiency with the same design posed several design challenges. One of the biggest and most basic was what to do with the wing. The longer the range, the better it was to have a bigger wingspan. Yet the opposite applied for shorter-range routes, where the typical mission required far less fuel and usually operated from smaller airport gates of 757/767 size rather than 777 size.
One possible solution studied was an optional wing “tip treatment,” which was essentially a large winglet to allow the SR span to be shrunk to about 164 feet, from the 187.9-foot span of the standard 7E7. Mike Bair acknowledged that solving the span issue was one of the “biggest complications” in the design process, and one that severely challenged Boeing’s one-plane-fits-all dream.
Huge production decisions also loomed in 2003, with Boeing facing the dilemma of where to actually assemble the 7E7. In March Bair said, “We are developing a list of criteria which we will use to evaluate the final assembly site, and it is in our interests to make that list as open a process as we can.”
While planning the assembly process for the 7E7, Boeing looked most closely at lessons learned on the 737. Lean assembly techniques and the implementation of a moving line had seen the assembly time of a 737 at Renton cut from twenty-two days in 2000 to just eleven days by 2008. Boeing was targeting a final cycle time of six days as it aimed to produce more than thirty 737s per month. The aircraft move along the line, complete with all the wheeled equipment around it, at about two inches per minute. Mark Wagner
Taking its cue from the Airbus production process, which involved the airborne delivery to a final production line of very large subassemblies from the partner sites around Europe, Boeing chose to evolve this for the 7E7. Parts from Boeing’s new and as yet undecided set of partners would be flown or shipped to an as yet undecided location somewhere in the continental United States, or even more astonishingly, elsewhere in the world. “It doesn’t necessarily have to be in the United States—those are the sort of things that are on our list to consider. We haven’t even ruled out multiple sites,” Bair said.
The move was a radical departure for Boeing, which had grown up around its two major commercial assembly sites in the Puget Sound area: Renton near Seattle, and Everett. Although an increasingly large number of big parts came into Puget Sound by sea and rail, including entire 737 fuselages from Boeing’s Wichita, Kansas, site, the basic production process remained unchanged from the days of World War II.
PARADIGM SHIFT
“Final assembly will look vastly different to today’s aircraft. We’ll be taking advantage of a moving line, plus a smaller number of highly finished large pieces,” promised Bair. Boeing was already laying the foundations for much of the change at the time by outsourcing more structural work, particularly