Engineering:Yackey Monoplane
| Yackey Monoplane | |
|---|---|
| |
| Role | Light three seat passenger or mail carrier |
| National origin | United States |
| Manufacturer | Yackey Aircraft Company |
| Designer | Wilfred Yackey |
| First flight | 1927 |
| Number built | 2 |
The Yackey Monoplane was an American three seat parasol monoplane flown in the late 1920s. Two prototypes had some success in the 1927 New York City - Spokane National Air Derby and orders were placed but a crash killed its designer and ended production.
Design and development
The Yackey monoplane had a parasol wing built around two spruce box spars with plywood skinning ahead of the forward spar. It used the popular Clark Y airfoil and had a constant chord with blunt tips. It was braced to the fuselage on pairs of parallel struts to the lower fuselage longerons, and a central, short inverted vee cabane to the top of the fuselage.[1]
It was powered by a 225 hp (168 kW) Wright Whirlwind J-5 9-cylinder radial mounted in the nose with its cylinders exposed for cooling. The fuselage was flat-sided apart from raised upper decking.[1] Both the cockpits were open, with the two passengers[2] placed side-by-side over the wing with entry via full-depth doors. The pilot sat just aft of the wing trailing edge, where a cut-out provided a wider upper field of view. Baggage or mail was placed in a large hold behind the pilot. Its fuselage tapered rearwards to a cropped-triangular fin with a comma profile, balanced rudder. The tailplane was semi-elliptical in plan and mounted on top of the fuselage, each side braced from below with a strut and a parallel wire and from above with a wire to the fin. Elevators were full and rounded, with a large gap between them for rudder movement.[1]
The Yaxley had fixed, conventional landing gear with large wheels, each fitted with brakes and on half-axles mounted on the lower fuselage longerons. Short, vertical legs were mounted on the forward wing struts which were reinforced at those points by diagonal struts to the wing centre-section. Drag struts sloped upwards to the root of the rear wing strut. Its spring-steel tailskid was steerable.[1]
Operational history
The two prototypes took part in the 1927 National Air Derby, a 24 hour race between New York City and Spokane.[1] One, piloted by Hamilton Lee, gained fifth place and a $500 prize.[3]
By October 1927 Yackey had rebuilt and reorganized his two factories for serial production at an initial rate of one in three weeks, moving to one a week at the start of 1928. They had firm orders for five.[1] However, these plans were abandoned after 4 October when Yackey died making a final test flight of a Monoplane before handing it over to its new owner. A newly reinforced wing bracing failed during the programme of aerobatics he routinely used in a final, personal test of all his aircraft.[4][5]
Specifications
Data from Aero Digest 1927,[1][6]
General characteristics
- Crew: One
- Capacity: Two passengers
- Length: 26 ft 2 in (7.98 m)
- Wingspan: 41 ft 2 in (12.55 m)
- Height: 8 ft 4 in (2.54 m)
- Wing area: 284 sq ft (26.4 m2)
- Airfoil: Clark Y
- Empty weight: 1,460 lb (662 kg) 2460
- Fuel capacity: 84 US gal (70 imp gal; 320 l)
- Payload: 1,000 lb (450 kg)
- Powerplant: 1 × Wright J-5 Whirlwind 9-cylinder air-cooled radial piston engine, 225 hp (168 kW)
- Propellers: 2-bladed Standard Steel
Performance
- Maximum speed: 140 mph (230 km/h, 120 kn)
- Cruise speed: 115 mph (185 km/h, 100 kn) at 1,600 rpm
- Stall speed: 40 mph (64 km/h, 35 kn)
- Landing speed: 40 mph (64 km/h; 35 kn)
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Horsefall, October, 1927, p.420
- ↑ Eckland, K. O. (6 June 2008). "Aircraft Ya - Yu". http://www.aerofiles.com/_yz.html.
- ↑ Horsefall, September 1927, p.382
- ↑ "Wilfred Yackey". http://www.fhproject.org/Histories/Maywood/Wilfred%20Yackey.htm.
- ↑ "United States Congressional Serial Set, Volume 9342". 1931. https://books.google.com/books?id=AsVGAQAAIAAJ&q=yackey+monoplane+crash&pg=RA1-PA2.
- ↑ Eckland, K.O.. "American airplanes: Y - Z". http://aerofiles.com/_yz.html.
Bibliography
- Horsefall, J.E., ed (October 1927). "The Yackey Monoplane". Aero Digest (New York City: Aeronautical Digest Publishing Corp): 420. https://archive.org/details/aerodigest1119unse/page/420/mode/2up.
- Horsefall, J.E., ed (September 1927). "1927 National Derby and Air Race results". Aero Digest (New York City: Aeronautical Digest Publishing Corp): 382. https://archive.org/details/aerodigest1119unse/page/382/mode/2up.
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