Theodore Mathews 48, of Oak Harbor died about 5:45 a.m. Saturday at Harborview Medical Center in Seattle. Mr. Mathews' single-engine plane crashed and caught fire south of Oak Harbor Friday afternoon.
A passenger, tentatively identified as his wife, Karen Ann Mathews, 43, died at the scene, Smith said.
Following the 4 p.m. crash Friday, Mathews was taken to Harborview's trauma center with serious burns, and died Saturday.
The couple reportedly had been preparing to land their 1942 fabric-covered Stinson aircraft on a private grass airstrip near their home in the Hastie Lake area.
The National Transportation Safety Board will investigate the crash, the Island County Sheriff's Office said.