Airship Hindenburg Flight. 1937 (May 1), Germany Flight postcard, franked by three stamps, cancelled by Brussels ''30.4.37'' Airport date stamp, lilac and red Flight markings, Frankfurt-on-Main ''1.5.37'' connection and Cologne ''3.5.31'' arrival ds, VF, Mi #63 I, Sieger unlisted, Est. $100-$150 (Image)