Flown for the ﬁrst time on Z4 April 1946, just three hours after the Mikoyan-Gurevich OKB‘s I-300 (MiG-9), the Yak-15 was to achieve the distinction of being one of only two service jet ﬁghters in aviation’s annals to have been derived from a piston-engined service ﬁghter (the other being the Swedish Saab 21R). Primarily the responsibility of Yevgenii Adler and Leon Shekhter, development of the Yak-15 began in May 1945, the all-metal second-generation Yak-3 airframe being used as a basis and enabling the ﬁrst of three prototypes to be completed in the following October. Taxying trials and short “hops” were performed, but ﬂight testing was delayed while the possibility of the jet efﬂux attaching to the fuselage at high incidences was explored in the TsAGIT-101 full-scale wind tunnel.
The Yak-15 retained most of the wing, rear fuselage, tail and undercarriage of the Yak-3, a new fuselage nose housing a Junkers Jumo 004B turbojet being introduced, and the main-spar being arched over the jetpipe. The Yak-15 was demonstrated over Tushino during Aviation Day on 18 August 1946, and two days later, on 20 August, the NKAP (People‘ s Commissariat for the Aircraft Industry) issued a directive that 12 additional aircraft be built to participate in the October Revolution Parade to be held on the following 7 November, 80 days later. Produced by hand, the ﬁrst of these ﬂew on 5 October and the last in time to participate in the Parade, which, in the event, was cancelled because of inclement weather.
State Acceptance testing was completed in May 1947, and, despite being structurally limited to Mach=0.68 below 10,500 ft (3,200 m), the Yak-15 was ordered into production at GAZ 153 as an interim type. One of the pre-series Yak-15s had meanwhile been adapted as a tandem two-seat conversion trainer under the designation Yak-21. The series Yak-15 carried an armament of two 23-mm NS-23 cannon and was powered by a Jumo 004B turbojet which had been adapted by I F Koliesov of the Lyulka bureau for manufacture at Kazan as the RD-10 with a rating of 1,967 lb st (892 kgp). Production gave place late in 1947 to the Yak-17 after completion of 280 Yak-15s.
- Max speed: 435 mph (700 km/h) at 8,200 ft (2,500 m), 500 mph (805 km/h) at 16,405 ft (5,000m).
- Time to 16,405 ft (5 000 m): 4.8 min.
- Max range: 317 mls (510 km).
- Empty Weight; 5,181 lb (2,350 kg).
- Loaded weight; 6,029 lb (2,735 kg).
- Span; 30 ft 2 1/4 in (9.20 m).
- Length; 28 ft 6 1/2 in (8.70 m).
- Height; 7ft 5 1/3 in (2.27m).
- Wing area: 159.85 (14,85m2).