S-5/S-5A, I.I.Sikorsky

Igor Sikorsky's pilot license (dated August 18, 1911 old style). The photograph shows Sikorsky at the controls of his S-5. Courtesy of and the National Air and Space Museum;

After the in-flight failure of Anzani engine (S-4 model) I.I.Sikorsky incorporated German built Argus engines, which was heavier but more reliable. Upper wing span was increased. second seat was added.

The S-5, first flown in April width="256" height="187" , was able for sustained flight up to an hour. Flying this plane I.I.Sikorsky obtained his pilots license and established four Russian records:

32k b/w as seen at "History of aircraft construction in the USSR", Vol.1 p.73

Few flights with passenger were performed on June 14, 1911.

The seaplane version S-5A more powerful had 60hp Gnome (Rhône) engine. It had very slim fuselage, but it was rugged enough due to plywood cover. First version had pair large ski-shaped float and small cylinder float under the tail.

Test flights by G.V.Alekhnovich proved that aircraft is underpowered and it was not accepted by Sea Department. Used later as a trainer.

36k b/w two-float S-5A hydroplane "History of aircraft construction in the USSR", Vol.1 p.134

Second version of S-5A seaplane had single large float, two small support floats under the wings and tail cylinder. 80hp Gnome provided more power, and aircraft proved to have better performance than 'Curtiss' biplanes and Farman-XVI. It was in active reconnaissance service in Revel (now Tallin) since September 1914.

32k b/w one-float S-5A hydroplane "History of aircraft construction in the USSR", Vol.1 p.134

Sources:

• 'Igor Sikorsky - The Russian Years' by K.N.Finne
• "History of aircraft construction in the USSR", Vol.1 p.73-74, 133-135;
• Short article(?) by Carl J. Bobrow found at RAP by A. Gretchihine.