01/31/2012. Remarks by Kees Kort: "By the typical form of the rudder, this is a post-WW I converted Thomas Morse S-4. After the war lots of Thomas Morse S-4 biplanes were sold on the second-hand market. About sixty were used till the end of the twenties when the machine did not meet the ever more stringent US air regulations.
Alike the pictured aircraft, many were converted with a 90 hp Curtiss
OX-5 water-cooled engine, and some got a second
passenger seat. Other 'civil' Thomas Morse S-4 machines were converted
to a side-by-side version with OX-5 by Yackey Aircraft Company. I do not have an explanation
for the marking 17 R6 on the side of the fuselage."