ZA002, Boeing's second 787 flight test aircraft, concluded a two week visit to Everett for an aqueous wash of its fuel tanks and departed Paine Field at 11:32 AM PT for a test flight that should have the aircraft flying for about six hours. The aircraft departed to the south, turned west, climbing to 25,000 feet then turned South down the Pacific Coast toward Oregon and on to Northern California.
The aircraft will spend the day testing the twin Trent 1000 engines and the oxygen analysis system (OAS), which is intended to measure the oxygen content in the fuel tanks while the nitrogen generation system (NGS) is in use. Guy Norris has an excellent rundown of the system and its origins.
The aircraft is expected to be back on the ground at Boeing Field, site of the company's flight test center, around 5:30 PM PT.