This image was acquired from
flickr. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
bell bellx bell aircraft vgw variable sweep wings variablesweepwings vsw swingwings swingwings experimental flight experimentalflight flight test flighttest xplane xplane allison allisonj general electric generalelectric ge general electric generalelectricj ge gej variable sweep wing variablesweepwing blackandwhite monochrome airplane