Boeing 787 Dreamliner - Mark Wagner [80]
Fatigue tests on ZY998 started in the first half of 2009 and were due to run for three years, with a goal of demonstrating 165,000 simulated flight cycles by 2012. Design life for the 787 was 44,000 cycles, with the target of achieving 88,000 cycles—two lifetimes—by certification.
SYSTEMS TESTS
The greater level of systems sophistication and integration on the 787 gave extra urgency to testing and ironing out the inevitable bugs, particularly in view of the tight development schedule.
To test the 787 systems to the full, Boeing equipped a series of laboratories within the existing integrated aircraft systems test facility by the Duwarmish River, west of Boeing Field. The facility had proved highly effective during the development of the software-intensive 777, and this time its role was expanded to work directly with several off-site test and development labs established by system partners around the world.
The integrated test vehicle formed a vital part of the 787 development and was designed jointly by Boeing and the suppliers. The seventy-five-ton hybrid test rig was made up of actual flight control and hydraulic system components, all of which were linked to three test benches of system software. Mark Wagner
The largest of these was the Hamilton Sundstrand aircraft power system integration facility (APSIF) in Rockford, Illinois. Hamilton was the largest single systems supplier on the 787, with eight major packages comprising 1,300 major components and requiring 1.5 million lines of software code. The APSIF was conceived as part of the company’s original proposal for the various systems, and ended up becoming a complete representation of the 787’s electrical systems, from generators to motors, laid out as they are in the aircraft, with all the actual cabling.
Set up on two floors occupying fifteen thousand square feet, the power generation, conversion, and consumption machinery was on the ground floor, while the avionics and data acquisition systems were upstairs. The lab was so realistic that a 787 APU was housed in a container just outside the lab to provide power. The lab also could run off ground power or generators mounted to 1,500-horsepower dynamometers simulating the engines. These were programmed with the assist/resist curves of the real engines to fool the starter/generators into thinking they were connected to GEnxs or Trent 1000s.
Power sources for the systems also were aircraft-identical and included four 250-kilowatt engine-mounted starter/generators and two 225-kilowatt starter/generators on the APU. Together they provided 1.45 megawatts of available electrical capacity via four main power buses. Two dual-redundant bus power control units managed the power distribution, directly as 235V variable-frequency AC or converted to 115VAC, 270VDC, or 28VDC. A bank of eight high-power motor controllers converted the high-voltage DC to the waveforms and frequencies required to drive the seventeen large motors.
Power consumers included four 75-kilowatt cabin compressors to provide air conditioning and cabin pressurization, plus two ram fans to move air through the environmental control system when “the aircraft” was stationary. Four 75-kilowatt motor-driven hydraulic pumps powered the flight controls and landing gear. On the upper floor were the overhead panels and flight displays required to power up the aircraft.
The site was electronically linked to Boeing, where test engineers were able to conduct tests of the integrated systems