|National origin||United States|
|Manufacturer||Sikorsky Manufacturing Company|
|First flight||23 August 1926|
The Sikorsky S-35 was an American twin-engined sesquiplane transport later modified to three-engines. It was designed and built by the Sikorsky Manufacturing Company for an attempt by Rene Fonck on a non-stop Atlantic crossing for the Orteig Prize. It was destroyed in the attempt.
 Design and development
The S-35 was designed as a twin-engined transport with a 1,000 mile range. During 1926 Rene Fonck, a French First World War fighter ace, was looking for a multi-engine aircraft to enter a competition to be the first to fly non-stop from New York to Paris, the prize was $25,000 offered by Raymond Orteig. Fonck had Sikorsky re-design the aircraft for three engines.
The S-35 was a sesquiplane with a fixed tailskid landing gear, it was modified to take three 425 hp (317 kW) Gnome-Rhône Jupiter 9A radial engines, these modifications took time to complete and the aircraft first flew on 23 August 1926 from Roosevelt Field. Sikorsky started a series of test flights but as none were at the maximum take off weight of 24,200lb, Sikorsky wanted to delay the transatlantic crossing until early 1927 but the promoters of the flight would not accept a delay and the aircraft was prepared for the crossing.
 Operational history
The first transatlantic attempt was scheduled for the 16 September but was abandoned after the aircraft developed a fuel leak. The next available break in the weather was to be the 21 September and the aircraft was fueled during the previous night from 50 barrels of gasoline, when the aircraft was weighed it was found to be 4,000lb overweight. Fonck with his co-pilot Lt Lawrence Curtin of the United States Navy were joined by a radio operator and a Sikorsky mechanic for the flight. In front of a large crowd at Roosevelt Field the aircraft gathered speed when the auxiliary landing gear broke away, the aircraft failed to get airborne and plunged down a steep slope at the end of the runway and burst into flames.  The two pilots escaped injury but the radio operator and mechanic were killed, the aircraft which had cost $100,000 was not insured.
Data from Best
- Crew: 4
- Length: 44 ft 0 in (13.41 m)
- Upper wingspan: 101 ft 0 in (30.78 m)
- Lower wingspan: 76 ft 0 in (23.16 m)
- Height: 16 ft 0 in (4.88 m)
- Wing area: 794 sq ft (73.8 m2) upper wing
- Empty weight: 9,700 lb (4,400 kg)
- Gross weight: 20,000 lb (9,072 kg)
- Powerplant: 3 × Gnome-Rhône Jupiter 9A radial engine, 425 hp (317 kW) each
- Propellers: 2-bladed, 10 ft 6 in (3.20 m) diameter
- Maximum speed: 65 mph (105 km/h; 56 kn)
- Endurance: 7 hours
- Service ceiling: 16,800 ft (5,121 m)
 See also