The Model D was a
biplane fitted with a wheeled
tricycle undercarriage. The construction was primarily of
spruce, with
ash used in parts of the engine bearers and undercarriage beams, with doped linen stretched over it. The outrigger beams were made of bamboo. Prevented by patents from using the
Wright Brothers'
wing warping technique to provide lateral control, and with neither the Wrights nor himself likely to have known about
its prior patenting in 1868 England, Curtiss did not use the ''June Bug's'' "wing-tip" aileron configuration, but instead used between-the-wing-panels "inter-plane"
ailerons, instead, as directly derived from his earlier
Curtiss No. 1 and
Curtiss No. 2 pushers. In the end, this proved to be a superior solution. Both the interplane and trailing-edge ailerons on these early aircraft did not use a hand- or foot-operated mechanism to operate them, but very much like the earlier
Santos-Dumont 14-bis had adopted in November 1906, required the pilot to "lean-into" the turn to operate the ailerons—on the Curtiss pushers, a transverse-rocking, metal framework "shoulder cradle", hinged longitudinally on either side of the pilot's seat—initially as straight metal tubes resting against the pilot's upper arms; and later achieved with "armrests" in a similar location; achieved the connection between the pilot and aileron control cabling. Almost all Model Ds were constructed with a
pusher configuration, with the propeller behind the pilot. Because of this configuration, they were often referred to as the "Curtiss Pusher". Early examples were built in a
canard configuration, with
elevators mounted on struts at the front of the aircraft in addition to a
horizontal stabilizer at the rear. Later, the elevators were incorporated into the tail unit, and the canard surface arrangement dispensed with, resulting in what became called the Curtiss "Headless" Pushers. In addition to amateur aviators, a Model D was purchased in April 1911 by the
Aeronautical Division of the U.S. Army Signal Corps as a trainer (S.C. No. 2), and by the
Navy as an airborne observation platform. A number of them were exported to foreign militaries, as well, including the
Russian Navy. On November 14, 1910,
Eugene Ely took off from USS
Birmingham in a Model D. This was the first time an aircraft had taken off from a ship. ==Variants==