Sikorsky S-39

Sikorsky S-39
A Civil Air Patrol S-39
Type:	Amphibious aircraft
Design country:	United States
Manufacturer:	Sikorsky Manufacturing Co.
First flight:	Mid-1929
Number of pieces:	21 (all versions)

The Sikorsky S-39 was a five-seat amphibious aircraft built in the late 1920s and early 1930s by the US manufacturer Sikorsky Manufacturing Co. , which was mainly used for civil purposes.

history

After the success of the S-38 , Sikorsky reduced its basic structure with the S-39 and created an aircraft for the emerging market of business aviation, which should also be of interest to air taxi companies in coastal regions. The original prototype received two 115 hp Cirrus Hermes engines with which the S-39 completed its first test flights in mid-1929. However, the plane crashed that same year after losing an engine.

The only 1YC-28

The S-39-A (also S-39A), which flew for the first time in early 1930 and used a Pratt & Whitney R-985 attached directly to the wing, had more success . This made the S-39 the first American aircraft to receive a type certification (ATC 340) with this engine. Despite the onset of the global economic crisis , twelve S-39-A were sold by the end of 1930 at a price of 17,500 US dollars each. Six more copies of the S-39-B introduced in 1931, which had larger tail surfaces, were sold to private operators. There was also a machine that was procured by the US Army Air Corps (USAAC) in 1932 and operated as the Y1C-28 (USAAC serial number 32-411). The testing of the aircraft at Wright Field (Ohio) quickly showed that the arrangement of wing and engine struts restricted the pilot's visibility so much that it was not possible to use it as a military transporter. In the mid-1930s, the aircraft was used under the changed designation C-28 as a liaison aircraft at the West Point Military Academy (New York).

Two S-39-B were retrofitted with 400 hp R-1340 Wasp radial engines, which meant a renewed type approval as S-39-C.

Osa Johnson in her Spirit of Africa

The last example was an S-39-CS (C Special) named Spirit of Africa , which was built in 1932 on behalf of the well-known explorers and photographers Martin and Osa Johnson . The paint of the machine corresponded to the stain camouflage of a giraffe. With this S-39 the Johnsons covered almost 100,000 km on their flights in Africa and East India .

S-39-B at the New England Air Museum

Some civilian S-39s were requisitioned by military services during World War II and used by the Civil Air Patrol (CAP) for search and rescue missions. These aircraft were neither given Air Corps serial numbers nor were they given a military designation for these S-39s. A restored CAP machine is currently (2017) in the New England Air Museum in Windsor Locks (Connecticut).

The only airworthy S-39 is an S-39-B with the registration number NC50V, which is currently (2017) in the inventory of the Fantasy of Flight Museum, but is not on display. The aircraft has a zebra paint scheme based on the Spirit of Africa and is named Spirit of Igor in memory of Igor Sikorsky .

Technical specifications

Parameter	Data
crew	1
Passengers	4th
length	9.68 m
span	15.86 m
Wing area	29.7 m²
Empty mass	1216 kg
Takeoff mass	1816 kg
Cruising speed	152 km / h
Top speed	184 km / h
Service ceiling	5490 m
Range	600 km
Engine	1 × nine cylinder - radial engine Pratt & Whitney R-985 Wasp Junior with 300 hp (221 kW); Two-blade metal propeller adjustable on the ground

See also

• List of aircraft types

literature

• ER Johnson: American Flying Boats and Amphibious Aircraft. McFarland and Co., 2009, ISBN 978-0-7864-3974-4 , pp. 70-72.
• ER Johnson: United States Naval Aviation 1919-1941. McFarland and Co., 2011, ISBN 978-0-7864-6269-8 , p. 145.

Web links

Commons : Sikorsky S-39  - collection of pictures, videos and audio files

• Information about the S-39 at goldenwingsmuseum.com (accessed February 9, 2017)
• Flight recordings including water take-offs and landings of the Spirit of Igor (accessed February 5, 2017)
• Overview of all Sikorsky fixed-wing aircraft

Individual evidence

1. ↑ List of Approved Type Certificates
2. ^ ER Johnson: American Military Transport Aircraft. McFarland and Co., 2013, pp. 56-58.
3. ^ John M. Andrade: US Military Aircraft Designations and Serials since 1909. 1979, p. 63.
4. ↑ Spirit of Igor on fantasyofflight.com (accessed February 8, 2017)
5. ↑ Website of the Spirit of Igor (accessed on February 8, 2017)