Boeing’s slow-selling 747-8 hasn’t struggled to gain market penetration for a lack of effort on the part of the company’s sales team, or, as program head Eric Lindblad would attest, a lack of ongoing performance improvements or technological innovation. In fact, today’s 747-8 weighs some 9,000 pounds less than the first example Boeing placed into service in 2011 and 2,000 pounds less than airplanes it delivered around a year ago. With further work, the company expects the weight to eventually drop by more than 10,000 pounds.
“We continue to make solid progress there,” said Lindblad. “As you take weight out you improve gas mileage, and that’s one of the ways that we influence the overall economics of the aircraft.”
Some of the weight savings comes from a performance improvement package (PIP) on the airplane’s GEnx-2B engines, introduced last December. The PIP, which includes a new low-pressure turbine design, redesigned high-pressure compressor airfoils, as well as an “upgraded” combustor and improved high-pressure turbine aerodynamics, improved engine efficiency by 1.8 percent, meaning today’s 747-8 operates some 3.5 percent more efficiently than the first to roll off the assembly line.
Further advances took the form of upgrades last December to the 747-8’s flight management computer (FMC) that improved navigational performance and step-climb efficiency, while reactivating the tail fuel tanks in the 747-8’s passenger version, the Intercontinental, extended its range to about 7,700 miles at a 467-passenger count.
Future Projects
Future projects center around what Lindblad characterized as an array of items that increase overall efficiency and would allow for routes between the Middle East and the West Coast of the U.S. or Hong Kong to U.S. East Coast routes. A route between Honk Kong and New York would require some 8,200 nm of range with reserves.
“We’re in the process of really taking pieces of the items that were on the list and incorporating those and if we end up with a campaign that needs that route structure we’ll move forward and do the full menu,” he said.
Some of those items would include aerodynamic changes that involve some of the fairings adjacent to the horizontal tail and an aerodynamic thinning of some of the scalloped areas of the thrust reverser. A decision to increase maximum takeoff weight would come at around the same time Boeing decides to change the aerodynamics on the wing-to-body fairing, which Lindblad described as a “fairly large-scale job.”
“So we’ll probably wait to see if we actually need that to get to the full 8,200-mile range,” he said.
Now some 31 months into service, the 747-8 fleet operates at a 98.9 dispatch reliability rate. Some of the “issues” customers still encounter include what Lindblad called interrupts from ground power to APU power and APU power to generator power, requiring crews to perform a restart sequence that could delay dispatch by “a few extra minutes.”
“We intended to exceed 99 percent [dispatch reliability] before the year’s out, and we pretty much know exactly which improvements we have to make to the aircraft that drive that reliability up and we’re working closely with our customers not only to receive the service bulletins and parts but to incorporate them into their fleets,” said Lindblad.
Of course, future fleets will benefit as well, and as the world cargo market shows signs of life after years in the doldrums, Lindblad sees the timing of the airplane’s maturation aligning nicely with Boeing’s expectations of a sales resurgence.
Sees Sales Resurgence
“We still expect the market to rebound as we’re starting to see some of the signs, and we’re really expecting aircraft sales to start to come into parity sometime in the 2016 time frame, [when] we’ll see the freighter sales pick back up…We’ve shoved capacity into the marketplace and they’re happy to take them, but they don’t necessarily put them all into service right away”
The cargo market grew by an annualized rate of some 4 percent in the first quarter of this year, just shy of the 5 percent annual rate Boeing projects for over the next 20 years.
Now building 747s at a rate of 1.5 per month, Boeing sold a total of 17 of the four-engine jets last year, representing nearly a 1:1 book-to-build ratio. Its backlog as of mid-June stood at 51 airplanes, accounting for roughly three years of production.
On the subject of production system stability, Lindblad drew attention to the fact that the line now runs roughly a day-and-a-half behind schedule, compared with four days a year ago. Boeing expects more efficiency to come from the planned use of a Flex Track automated drilling and riveting machine, now in place on the 777 line, for lap joints and circumferential joints on the 747-8 fuselage. “We’re not done investing not only in the product itself, but the production system, which is important to me to validate that there’s a lot of time left on this aircraft,” concluded Lindblad.
