Boeing has begun powering up 787 avionics, hydraulic, flight control and other systems for the first time using real "aircraft" power, representing a major milestone towards completing integration of all the systems before actual assembly, writes Guy Norris.
The tests involved pumping power to laboratories from turn stands to produce the equivalent output of the engine-mounted 250kVA variable frequency starter generators on the 787's General Electric and Rolls-Royce engines.
"We've had two rounds of doing that," says 787 systems director Mike Sinnet, who adds: "For the first time these laboratories are seeing actual ship's power."
The power connected the propulsion integration laboratory and the integrated test vehicle (ITV), both sites within the integrated aircraft systems laboratory in Seattle.
In the propulsion integration laboratory, the tests enabled Boeing to simulate engine starts, while in the test vehicle "we powered the hydraulic systems with variable ship's power, in other words varying the power provided as a function of engine speed as determined, in turn, by throttle position in the ITV," says Sinnet.
Boeing estimates around 25% of integration testing has been completed, but acknowledges issues have been uncovered. "The goal is to find as many problems as early as we can. We are essentially on the number of problems we thought we'd be at. That's a couple of thousand integration problems and so far we've fixed a couple of thousand problems," says Sinnet.
He adds: "The good news is that the bulk are integration issues, rather than problems that should have been picked up by suppliers during bench testing."
Source: Flight International