Activated: August 29, 1942; Deactivated: October 7, 1943. Seattle Filter Center.
July 27, 1939: Air warning Service Post No. 42 reports by telephone to Puget Sound Power and Light Company at Skykomish. (Letter to Supervisor of the Snoqualmie National Forest from Headquarters Harbor Defenses of Puget Sound and 14th Coast Artillery)
1941: The lookout house was moved to Maloney Ridge.