On June 21, 1974, during the afternoon, Seattle Police Officer James H. St. Delore died in the line of duty. Officer St. Delore was a Police Helicopter Pilot in "Air 3," and the Observer was Officer James M. Forbes. The officers were responding to a shooting in the south end of the city. As they flew above Beacon Hill, the helicopter collided with a Cessna 150 that was landing at Boeing Field. The mid-air collision killed both officers and the two occupants of the plane.

Officer James H. St. Delore was survived by his wife Phyllis, son Jeffery, and daughter Jennifer.