Max Efficiency Must Extend to Boeing’s 737 Production Line
Calling this the year of design execution for the Boeing 737 Max, program chief Keith Leverkuhn finds himself immersed in the challenges of orchestrating the re-engined narrowbody project to support a factory production rate due to rise to 47 a month around the time the first Max 8 enters service in 2017.
During a recent briefing at Boeing offices in Everett, Washington, Leverkuhn reported that the program will have released 25 percent of the design by the middle of this year, right around the time the first full CFM Leap-1B engine goes to test. Expressing “comfort” in the airplanes’ roughly 3,600-nm range, he said he foresees no further changes in weight or payload specifications. Meanwhile, Boeing has so far completed 150,000 hours of laboratory development in support of all the integration of the new systems, new flight deck and new fly-by-wire spoilers. “We’re also doing a lot of mockup work along with the detailed design in our Catia 3-D system because we know we’ve got to be able to produce this airplane at high rates,” he said.
Leverkuhn explained that to fit the new designs into the present production scheme while maintaining flow times, Boeing must consider how many more or fewer minutes each part might take to build than the one it replaces. “So what we’ve done through each of the teams, whether it’s the structures team or the systems team or the propulsions team, is make sure they get budgeted a certain amount of time for all their designs as they move through the factory, so that really drives what kind of designs they can bring into the facility,” he added.
One design element on which flow time management undoubtedly will prove critical involves the engine inlet. In a departure from Boeing’s previous practice, the company has decided to perform both the detailed design and the build itself at Boeing Propulsion in Charleston, South Carolina, site of a new assembly facility due for completion by the end of the year. “As the engine technology continues to develop, the desire will be for larger fans, smaller cores, and I think that the people who’ve got the ability to artfully incorporate those engines that are going to look very different from the engines today…are going to have a competitive advantage,” said Leverkuhn. “So I think us bringing some of that capability back in, starting on the Max, is going to be important for our longer play, our longer [term] future.”
In Renton, Washington, where Boeing now builds the NG and will continue to build the Max, the company has begun mounting tooling in the systems installation (SI) area. It also has begun to “provision” for moving items out of the area chosen for a third assembly line, where it plans eventually to move production of the NG as the Max integrates into the two existing lines.
By May 1 the 737 Max had drawn orders for 1,939 units from 37 customers since program launch in 2011 and, according to Leverkuhn, the company stands “not too far away from celebrating its 2,000th order.” Boeing claims that since the launch of the Max it has drawn what amounts to 55 percent of the market in which it competes with the Airbus A320neo. In absolute numbers, the Neo still holds a significant lead, however.
“I’m hoping that with the team we can do a little celebration in the coming days, when we hit the 2,000 mark, and then it’s back to work,” he said.
Boeing has nearly finished with the “prototyping” of a distinctive new winglet, which feature upward and downward-directed composite airfoils joined with a metallic center piece designed to improve fuel efficiency by at least 1.5 percent. As one of the major aerodynamic differences between the 737NG and 737 Max, the new winglet in particular represents an item Boeing must design with high rates of production in mind. “It’s coming together very, very well, which gives us good confidence not only in the performance of the aircraft, but being able to produce it at rate,” concluded Leverkuhn.