Top speed 230 km/h Length 6.97 m | Wingspan 8 m First flight 1924 | |
The Letov Š-13 was a single seat, single engine fighter aircraft designed and built in Czechoslovakia in the early 1920s. A biplane, it had aerodynamically thick wings which were originally cantilever structures, though interplane struts were later added. Only one was produced.
Contents
Design and development
The Letov Š-13 was designed as a cantilever biplane, its Zhukovsky airfoil wings thick enough in section to allow internal bracing. In other ways it much resembled the 1923 Letov Š-7. The wings, mounted with modest stagger, were straight edged with constant chord and blunt wing tips. The slightly broader chord upper wing was braced to the fuselage with a cabane formed, on each side, by a forward parallel pair of struts from the mid-fuselage and a rear inverted V pair from the upper fuselage. Only the lower planes carried ailerons.
Both the Š-7 and the Š-13 were powered by a Škoda licence-built Hispano-Suiza 8Fb, a 300 hp (224 kW) water-cooled V-8 engine. Letov had experienced cooling problems with it in the Š-7 and so the ring shaped radiator proposed originally for the Š-13 was dropped and replaced from the start with the transversely mounted, circular cross-section ventral radiator successfully tested on the modified Letov Š-7a. The Hispano drove a two blade propeller with a domed spinner. Behind the engine the fuselage had an oval cross-section, with the single open cockpit partially under the wing trailing edge which had a shallow cut-out to enhance his view. The fuselage tapered rearwards to a point behind the tail control surfaces. The cropped, straight tapered horizontal tail was mounted on the fuselage centre line; the fin and rudder, larger than on the Š-7, were also straight edged. The Š-7 had a fixed, single axle conventional undercarriage, with mainwheels on cross braced V-struts, assisted by a tailskid.
The Letov Š-13 first flew in 1924 in cantilever configuration but during the early flight trials concern about wing strength led to its conversion into a single bay biplane by the addition of a pair of interplane struts. These were initially N shaped but later changed to Vs. The trials demonstrated generally good handling characteristics but stability problems brought an end to development.
Specifications
Data from Green and Swanborough p.333
General characteristics
Performance