Boeing Dreamliners complete key flight tests
Successfully concluding one of the most heart-racing phases of the 787's flight test program, Boeing has completed flutter tests on Dreamliner No. 1. Its Dreamliner No. 2 also completed a separate flight-test milestone analyzing the aerodynamic stability of the plane as it flew close to the ground.
Seattle Times aerospace reporter
Boeing has completed flutter tests on Dreamliner No. 1, successfully concluding one of the most heart-racing phases of the 787's flight-test program.
In a company blog posting late last week, Marketing Vice President Randy Tinseth also said Dreamliner No. 2, flying in Victorville, Calif., completed a separate flight-test milestone analyzing the aerodynamic stability of the plane as it flew close to the ground.
Both sets of tests went well, with the pilots finding the planes handled as predicted in simulations.
"We couldn't be more pleased with the performance of the 787," said Tinseth. "The 787 test fleet has now been cleared to fly throughout its full flight envelope."
Once the Federal Aviation Administration (FAA) has validated the results, Boeing anticipates receiving "Type Inspection Authorization," which means FAA technical teams will join the test flights and the flight-test program moves into its next phase: certification testing.
Flutter testing is used to detect potential for a catastrophic phenomenon, where aerodynamic forces on the airframe body and control surfaces cause a rapid, self-feeding shaking that could destroy the structure.
For safety, the design of the airplane must damp any such vibrations, not amplify them.
During flutter testing over the state in the past two months, Dreamliner No. 1 flew at altitudes above 43,000 feet, dived at very close to the speed of sound (Mach 0.97), and reached airspeeds as high as 405 knots.
Meanwhile, Dreamliner No. 2 completed "ground effects" testing over the last two weeks at Victorville, which has a very long runway and uncluttered airspace.
The tests investigated how flying close to the ground affects the plane's aerodynamics and handling during takeoff and landing.
With these more dangerous test phases completed, pilots now will explore the extremes of the flight envelope, including hot weather, cold weather, high altitude, over-speed conditions, hard landings and engine-out conditions.
Other tests will calibrate the jet's performance in terms of fuel burn and noise.
Dominic Gates: 206-464-2963 or firstname.lastname@example.org