First flown in 1930, the Heinkel HD 42 was a seaplane trainer based on the old HD 24 and built initially for the covert military Deutsche Verkehrsfliegerschule (DVS). This is believed to be the third HD 42b, later redesignated as an He 42B (c/n 374 subject to confirmation). Markings indicate a 1934 or 1935 date. Location is likely Warnemünde.