In 1907, Alberto Santos Dumont improved the 14 Bis with another biplane, the number 15.
Six original, period photographs of issue number 15.
Authors: Rol & Cia, Branger.
France, 1907.
Approximately 12 cm x 17 cm.
Notes in French on the back.
Perfect condition.
Santos Dumont's No. 15 was an ambitious biplane prototype developed in 1907, shortly after the success of the 14-Bis. Initially powered by a 50 hp Antoinette engine mounted above the upper wing, the aircraft had large wingspan (11 meters) and extremely narrow wings, with a chord of only 60 cm, totaling an area of 13 m². These wings were divided into three sections by vertical surfaces and featured a pronounced dihedral, like the 14-Bis, as well as ailerons positioned in front of the wings for lateral control. The covering was made of Okoumé plywood only 3 mm thick, demonstrating the pursuit of lightness and efficiency. The landing gear consisted of a single wheel at the front junction of the lower wing, while the tail was supported by two long bamboo booms fixed laterally with steel cables. After being damaged during taxiing tests on March 27, 1907, the aircraft was repaired and fitted with a powerful 100 hp Antoinette V-16 engine, but despite the modifications, the aircraft never managed to complete a successful flight.
These photographs of Santos Dumont's No. 15 are of great historical and technical interest, as they clearly show the construction and testing of one of the Brazilian inventor's most ambitious projects after the success of the 14-bis. It is fascinating to observe the details of the biplane, with its narrow, long wings reinforced by vertical surfaces, the Antoinette engine mounted high, and the daring landing gear configuration with a single front wheel. The images show everything from meticulous assembly to ground tests, with Santos Dumont and his team alongside the aircraft, revealing both the experimental spirit and the elegant aesthetics of his creations. These are extremely rare records of a poorly documented phase of his career, in which he sought new advancements after conquering the skies of Paris in 1906.
