Boeing's fleet of 787 flight test aircraft remains grounded after an electrical fire occurred during a flight on Monday. During the approach to land in Laredo, Texas, ZA002 lost primary electrical power due to the fire. As a result, the Ram Air Turbine, a wind driven power generator, was automatically deployed and the crew was able to complete a safe landing.
The company says a failure in a power panel led to a fire involving an insulation blanket. The panel, called the P100 panel, receives power from the left engine and distributes electricity to an array of systems. The company says auxiliary power from the Ram Air Turbine, as well as the right engine and batteries provided power as designed.
The company hasn't directly commented on the loss of flight instruments reported on Monday, only saying the crew remained in positive control of the airplane at all times and had the information needed to perform a safe landing. Like all commercial airliners, young and old, the 787 has several redundant flight instruments. In the event a primary flight display is lost, other glass panel displays in the cockpit (on separate electrical systems) will display the information needed for the pilots to fly.
The flight controls are also powered by redundant systems. Three separate hydraulic systems power the flight controls on the wings and tail. Two of the systems receive power from the engines, and a third receives power from a separate electrical source. Only one of the power sources is needed to safely fly the Dreamliner.
Boeing says there was significant damage to the P100 panel and molten metal was found in the area which is located in the aft part of the aircraft, just behind the wing and underneath the cabin floor. Once the fault in the panel cleared, the insulation self-extinguished. The company says it will determine whether or not the surrounding systems or aircraft structure were damaged during the event in the coming days.
The airplane maker hasn't said whether the fire and the resulting grounding of the test fleet will result in another delay in the delivery schedule for the 787 Dreamliner. Boeing still has a significant number of flight tests to complete before receiving certification for the composite airplane. The first aircraft was expected to be delivered to All Nippon Airways in early 2011.
Photo: Boeing
