By Eric M. Johnson
SEATTLE (Reuters) - A U.S. military plane assigned to a Washington state Naval Air Station on Whidbey Island crashed on Monday morning during a routine training flight, killing all three crew members on board, Navy officials said.
The plane, a Northrop Grumman EA-6B Prowler, a twin-engine electronic warfare aircraft, went down sometime before 8:45 a.m. local time in Lincoln County in eastern Washington state, base spokesman Mike Welding said.
"It was flying out there. I don't know exactly what it was doing," Welding said. "Everything is really preliminary at this point."
The Navy said its personnel were investigating the crash in the rural area roughly 50 miles west of Spokane, where the crew had been conducting a routine training flight.
The base where the plane was assigned is located on Whidbey Island in the Puget Sound, north of Seattle. The plane crashed roughly 10 miles from Harrington. The Navy was withholding the names of the dead until after their families are notified.
The Northrop Grumman EA-6B Prowler's main use is to support air and ground troops by disrupting communications and obtaining tactical electronic intelligence within a combat area, according to the aircraft's maker.
Stan Dammel, the manager of a local airport who surveyed the crash site from his own aircraft, said he saw a deep patch of scorched earth and scattered debris.
"It just looked like an explosion," Dammel said.
Washington state Governor Jay Inslee thanked the aviators for their service.
"I know all Washingtonians join me in sending condolences to the crew's families and to their fellow service members whose duty to country often puts them in danger's way," Inslee said in a statement.
(This version of the story corrects location of crash in the fourth paragraph to west, from east as reported earlier, of Spokane; the error also occurred in Update 2.)
(Editing by Cynthia Johnston, Bernard Orr and Dan Grebler)