420th Night Fighter Squadron - Northrop P-61A-10-NO Black Widow 42-39368, IV Fighter Command, Hammer Field, California.  This is identified as a IV Fighter Command training aircraft by having its serial numbers painted on the underside of its wings.
United States Army Air Forces
1944
Campbell &amp; Pape, 1994, Northrop P-61 Black Widow: The Complete History and Combat Record, Schiffer, <a href="//commons.wikimedia.org/wiki/Special:BookSources/0887407382" title="Special:BookSources/0887407382">ISBN 0887407382</a> (Photo Credit given as USAAF photo)