Home Archive Search Media Media-418452.jpg FRE 8945 IMAGE Download Image By downloading this image, you are agreeing to our Terms and Conditions A prototype B-17 Flying Fortress (serial number X13372) in 1935. Handwritten caption on reverse: '4581, Boeing 299, X13372, 1935.' Revisions Date: 2 Feb 2015 10:00:10 ContributorAAMChangesAAM ingestSourcesIWM, Roger Freeman Collection