Fokker F-11

Fokker F-11
Type:	Traffic - amphibious aircraft
Design country:	United States
Manufacturer:	Fokker Aircraft Corporation
First flight:	1928
Number of pieces:	7 or 6

F-11, 1929

The Fokker F-11 (also F.11, internally Model 9 ) was an amphibious aircraft made by the US manufacturer Fokker Aircraft Corporation in the late 1920s. Fokker used its own naming sequence for its aircraft built in the USA. See e.g. B. the F-10 as the forerunner of the F-11.

history

Anthony Fokker had already developed some double-decker flying boats and amphibious aircraft for the Dutch Navy in the 1920s, but these were not adopted for military use. These specimens were the BI , B.II and B.III . Fokker hoped to meet with interest in the USA at least for the B.III. The aircraft was brought by ship to the Fokker factory in the USA, where it was converted into a civil version B.IIIC. It was then sold to Harold Vanderbilt , dubbed the Flying Yacht . However, no further construction contracts followed.

Fokker began with the construction of a shoulder-wing monoplane amphibious aircraft, which was to be propelled by a 525 hp Wright Cyclone R-1750 radial engine with a pusher propeller mounted on pylons above the fuselage . The prototype, which still used the standard wings of the Fokker Universal , had its first flight in 1928. According to another source, the wings of a Fokker F-14 were used. However, the series machines received a newly designed wing. Fokker built the all-metal hulls in the Netherlands and shipped them to the USA for final assembly. The high sales expectations were not fulfilled, so that of the 20 fuselages produced, only six could be completed and sold as aircraft. Since the actual target group of airlines showed little interest, most of the specimens went to financially strong buyers as 10-seater luxury versions ( flying yacht ). The boat builder Garfield Wood was one of them .

The US Army Air Corps (USAAC) tested an F-11 under the military designation Y1C-16 , but judged it to be unsuitable for its intended purpose.

The last two units received a modified engine equipment as F-11AHB with a Pratt & Whitney Hornet (575 HP), and an F-11 was converted to a pulling propeller as a test. The version with a Hornet engine was named B.IV in the Netherlands, although it never flew there. Tests with a twin-engine version with engines in tandem were also carried out. This 10-seat variant was used by Anthony Fokker as his personal plane.

An F-11 was exported to Canada, where it had an accident on a lake in 1935. A rescue team from the Aviodrome brought the front fuselage of the machine to the Netherlands in 1992.

construction

The fuselage structure consisted of riveted duralumin sections in lattice construction, which were clad with Alclad panels. The first two or three planes still had new types of fuselage outriggers that carried the main landing gear wheels at the ends . When landing in water , the booms could be swiveled up a little and serve to stabilize the position. However, this technique does not seem to have proven itself, as all subsequent machines received conventional support floats in the middle of both wings.

The unit price was initially $ 42,000, which was lowered to $ 33,775 in June 1930.

variants

F-11A

Starting version with a Wright Cyclone with 525 hp

F-11AHB

increased all-up weight, a Pratt & Whitney Hornet B with 572 hp

Demonstration aircraft

Unique piece with two engines in tandem, similar to Dornier Wal

Technical specifications

Parameter	F-11A data	F-11AHB data
crew	2
Passengers	4 to 5 (max. 8)
length	13.73 m
span	18.00 m
Empty mass	2020 kg	2300 kg
payload	1100 kg	969 kg
Cruising speed	152 km / h	157 km / h
Top speed	179 km / h	186 km / h
Landing speed	80 km / h	88 km / h
Summit height	3500 m	3350 m
Range	640 km
Engines	1 × Wright R-1750D Cyclone nine-cylinder radial engine with 525 HP, three-blade metal propeller, adjustable on the floor	1 × Pratt & Whitney Hornet B with 575 hp

Related developments

The General Aviation PJ, which was still designed by Fokker and built by General Aviation, was based on the structural design of the F-11, but had two engines and overall slightly larger dimensions.

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. 129-131
• Bart van der Klaas: Fokker's American Heydays . In: AIR Enthusiast No.68, March – April 1997, pp. 2–15
• Joseph P. Juptner: US Civil Aircraft Series. Volume 3, Aero Publishers, 1966, no ISBN, pp. 68-70

Web links

Commons : Fokker F.11  - collection of pictures, videos and audio files

Individual evidence

1. ^ ^{A b} E. R. Johnson, 2007, p. 129
2. ↑ JP Juptner, 1966, p. 70
3. ↑ Photos of BI to B.III on www.fokker-history.com (accessed on May 14, 2019)
4. ↑ Bart van der Klaas, 1997, p. 6
5. ↑ ER Johnson, 2007, p. 130
6. ↑ JP Juptner, 1966, pp. 68-70