Home Archive Search Media Media-418497.jpg FRE 8990 IMAGE Download Image By downloading this image, you are agreeing to our Terms and Conditions A US Navy PB-1W variant B-17 Flying Fortress (Bureau Number 77230) of Experimental Squadron VX-4, fitted with APS-20 radar, in flight 1947. Revisions Date: 2 Feb 2015 10:00:13 ContributorAAMChangesAAM ingestSourcesIWM, Roger Freeman Collection