|FIGHTER, INTERCEPTOR||Virtual Aircraft Museum / USSR / Russia / Sukhoi|
Development of a single-seat interceptor fighter providing better supersonic performance while (initially) preserving a fundamentally similar wing was begun as the T-5 in the late 'fifties. This was a larger aircraft than the preceding T-43 and was powered by paired Tumansky R-11 turbojets with lateral air intakes. Retaining the tailed-delta configuration and 57° sweepback at wing quarter chord, the interceptor was built as the T-58 prototype and flown on 30 May 1962, and, as the Su-15, 10 examples participated in the July 1967 air display at Domodedovo. The initial version, effectively confined to a large pre-series for service evaluation, possessed a wing similar to that of the Su-9 and Su-11, with some 30cm removed adjacent to the fuselage each side. The Oryol-D Al radar and two R-8 AAMs were fitted, and power was provided by two R-11F2S-300 turbojets each rated at 3900kg and 6200kg with max afterburning. The virtually pure delta wing gave place on the next version, the Su-15T (the suffix signifying introduction of Taifun radar), to a cranked leading edge with outboard sweepback reduced to 47°, overall span remaining unchanged. Su-15T production was limited to 10 aircraft delivered during 1969.
A V/STOL technology demonstrator derivative, the Su-15VD (vertikal'nye dvigateli, or vertical engines), was demonstrated at Domodedovo in July 1967, this having a trio of 2350kg Koliesov RD-36-35 lift engines mounted vertically in the centre of the fuselage. The definitive wing appeared on the Su-15TM (Taifun modifikatsiya) which became the major production version in 1972 and achieved operational status in the second half of 1973. This introduced a further variation of the cranked planform with a span extension of 60cm, the improved Taifun-M radar, and Gavrilov-developed R-13F-300 turbojets rated at 4237kg and 6600kg with afterburning. Armament, too, was upgraded, two additional wing pylons being introduced inboard and a pair of IR-homing R-23TE and two radar-guided R-23RE AAMs normally being carried. Twin pods each containing a twin-barrel 23mm cannon could be carried side-by-side on fuselage pylons. From 1975, the conical radome was replaced by one of ogival shape, production of the Su-15TM ending in the late 'seventies after manufacture of some 1,500 interceptors of this type.