Boeing 787 Dreamliner - Mark Wagner [49]
Set up alongside the ITV, the aircraft energy management (AEM) lab simulated engine-generated power using dynamometers. In a similar way to Hamilton Sundstrand’s APSIF site, the AEM exercised the aircraft’s full and complex power system—probing it primarily for power quality and seeking out potential problems. Mark Wagner
In the end, after competitive bids and several down-selects, a team of just over thirty major (Tier 1) companies was created to develop the systems and structures for the 787, compared to hundreds on previous efforts. Under the new system the partners performed far more of their own design, development, and manufacturing while working closely with Boeing’s Life Cycle Product Team (LCPT) organization.
A total of eight major LCPTs were created covering the fuselage, propulsion, services, interiors, production, integration, and systems, and one for the wing, empennage, and landing gear. “Each is responsible for the entire life of that part in the aircraft,” said Sinnett who led the systems LCPT. “In previous programs I’d have had responsibility for the engineering design, then I’d have turned it over to production.” Beneath each Tier 1 name was a subset of suppliers to the particular part or system being provided by that team. This fundamentally different approach made Boeing more of a product integrator, and allowed it to focus on its prime role of final assembly while permitting its partners to focus on their expertise in developing subassemblies and systems. In another departure from the past, the LCPTs also formed a Partner Council, which held meetings to share progress and expertise to help overcome problems.
ELECTRIC JET
By far the most radical step in the 787 systems story was the decision to make it the most “all-electric” jet ever developed. “It’s probably the biggest change to the systems architecture of any aircraft,” said Sinnett, who explained that the move was made mainly to improve engine efficiency. A myriad of systems normally powered by air bled from the engines were instead electrically powered.
“Our aircraft does not draw as much horsepower off the engine in cruise so it doesn’t burn as much fuel. If you look at the extraction profile you see the amount of power you pull off is just what you need, so the engine isn’t working any harder than it needs to. We’re only getting what we need, and we only use what we generate,” said Sinnett. This was no easy trick to pull off. Even the highly sophisticated “more electric” systems on the Lockheed Martin F-35 Joint Strike Fighter, the first new-build Western fighter design of the twenty-first century, could not do this and instead dumped excess energy into its fuel, which acted as a heat sink.
In keeping with the more-electric-systems theme, an electrically based deicing system developed for the rotor blades of the Bell-Boeing V-22 Osprey as well as for the AgustaWestland AW101 was selected for the 787. Here a V-22 dazzles the crowds at the 2006 Farnborough Air Show. Mark Wagner
Gear actuation was software-controlled rather than mechanically linked, enabling faster extension and retraction sequencing. This also helped cut drag and therefore could be factored in as a weight benefit. The landing gear actuation package includes an emergency, 3,000 psi alternative landing gear deployment system that opens the doors, releases various actuators, and then locks into position, all within seconds. The gear actuation system, along with the rest of the main landing gear, also was later tested in the landing gear actuation system (LGAS) test rig at Everett. Mark Wagner
Although the 787 main gear uses Boeing’s classic double-brace design, the braces themselves are made from composite materials—another first for a commercial jetliner. Together the two-part drag brace and side brace help spread the impact loads at the gear anchorage points where they attach to the composite wingbox. Based on a Messier-Dowty–developed woven fiber composite manufacturing process, the parts are made by U.S.-based