If you see a huge Boeing 777 skimming low over the waters of the Strait of Juan de Fuca or over the wheat fields of Eastern Washington this week, don’t be alarmed that you’re about to witness a plane crash.
Boeing is testing upgraded components in its ground proximity warning system and it needs to try out those new features under actual conditions.
The system is designed to warn pilots that they’re flying dangerously close to the ground. The ground proximity systems were created to make pilots who were either distracted with other issues or who lost awareness of their location while navigating through rough weather or poor visibility aware of their nearness to the ground.
The system also warns pilots of wind shear, a condition in which the wind abruptly changes direction, potentially causing a plane to suddenly lose altitude close to the ground.
The test aircraft will be flown at 600 to 700 feet above water and ground to test its warning abilities. In addition to flying over the strait and Eastern Washington, some testing will be done near Everett’s Paine Field where the test plane is based.
Meanwhile, Boeing Monday performed routine tests on a 787 flight from Paine Field to Moses Lake and back. Those tests had no direct connection with the battery certification tests Boeing expects to conduct later this week with a 787.
Fifty 787s have been grounded worldwide since January when battery fires aboard two 787s caused concern that the lithium batteries were a hazard to flight safety. Boeing hasn’t discovered the cause of those two fires, but it has proposed a series of safeguards to prevent future fires and to keep burning batteries from damaging the plane. Those safeguards include new internal insulation between battery cells, a new stainless steel box to house the batteries and a venting system to exhaust smoke outside the jets.