Su-27

Sukhoi · Soviet Union · first flew 1977 · fighter

The Su-27 Flanker is a large, long-range twin-engine, twin-fin air-superiority fighter and the basis of a vast family of Sukhoi combat aircraft.

Recognition (WEFT)

W — WingsMid-mounted, swept
E — Engines2 × turbofan, fuselage-mounted
F — FuselageBlended fuselage with big LERX
T — TailTwin fin

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Spot it by:

Identify it by its large size, blended wing-body with prominent leading-edge root extensions, two outward-canted fins and two widely spaced engines with a gap between the nacelles.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

First flown in 1977 and in service from 1985, the Su-27 was designed to match the F-15 with exceptional range, agility and a powerful radar. Its blended lifting fuselage and relaxed stability gave it superb manoeuvrability, demonstrated by the Cobra at airshows.

Variants

The Flanker spawned an extensive family including the two-seat Su-30, the strike-optimised Su-34, the canard Su-33 and Su-35, and Chinese derivatives such as the J-11. It is one of the most successful fighter dynasties of its era.

Where you'll see it

A front-line Russian and widely exported fighter, the Su-27 and its Su-30 cousins have displayed at RIAT Fairford, thrilling UK crowds with low-speed manoeuvres. The basic Su-27 has never served a Western air force.

In depth

The Su-27's design was driven by an intelligence report. In 1972, Soviet intelligence obtained technical details of the US Air Force's F-15 Eagle programme, which revealed an aircraft of far greater capability than the Su-15 and MiG-23 then in Soviet service. The response was immediate and thorough: two parallel programmes, TsAGI (the Central Aerohydrodynamic Institute) and Sukhoi's OKB, began work on what would become the Su-27. The target was explicit — match or beat the F-15 in every parameter including radar range, combat persistence, and sustained turn rate.

The key aerodynamic innovation was the blended wing-body, or 'ogival' fuselage, in which the wing and fuselage form a single lifting surface rather than a distinct fuselage carrying a separate wing. Combined with large leading-edge root extensions (LERXes) that generate powerful vortices over the inner wing at high angle of attack, this gave the aircraft a maximum lift coefficient substantially greater than the F-15's. The fly-by-wire flight control system was designed to allow the aircraft to operate at angles of attack beyond the normal post-stall region — a capability demonstrated publicly as the 'Pugachev Cobra', in which the nose pitches to ninety degrees or beyond before recovering to level flight, at the 1989 Paris Air Show by Viktor Pugachev. The manoeuvre has no direct tactical utility but demonstrated that the flight control laws permitted sustained operation at angles of attack where almost every other fighter would depart controlled flight.

The Su-27's combat history is spread across multiple conflict zones but centres on Ethiopia's war with Eritrea (1998–2000), in which Ethiopian Su-27s fought Eritrean MiG-29s in the only air battles in history between opposing aircraft of the Flanker and Fulcrum families. Ethiopian pilots, partly trained by former Eastern Bloc instructors, achieved a kill ratio of approximately four to one, downing at least four MiG-29s for no confirmed Su-27 losses. The engagements validated the R-27 medium-range missile as a reliable weapon and demonstrated that pilot training quality was at least as significant as aircraft capability at broadly similar performance levels.

In the 2022 Russian invasion of Ukraine, Su-27s and their Su-30 cousins were among the most contested assets in both air forces. Ukrainian Air Force Su-27s — some upgraded with Western avionics and AIM-120 AMRAAM compatibility — engaged Russian aircraft throughout the conflict. The air battles that resulted were analytically murky due to information warfare on both sides, but it is confirmed that Su-27-family aircraft were lost by both sides to air-launched missiles and surface-to-air missiles. The conflict demonstrated the continuing relevance of the Flanker airframe even against newer threats.

The Su-27's primary rival, the McDonnell Douglas F-15 Eagle, differs in several visible ways despite near-identical performance envelopes. The F-15 carries twin fins that are nearly vertical, while the Su-27's fins are canted slightly outward. The F-15 has large rectangular fuselage inlets far forward under the wings, while the Su-27's inlets are positioned under the LERXes with a distinctively different shape from below. From above, the Su-27's unbroken wing-body blend is immediately distinctive compared to the F-15's visually separate fuselage and wing. At long range, both appear as large, twin-finned, twin-engine fighters — the Su-27's longer, lower fuselage with more distance between the fins distinguishes it.

For UK spotters, genuine Su-27-family aircraft visit RIAT Fairford with some regularity as display aircraft from Ukraine, Kazakhstan, and historically Russia before 2022. The Ukrainian Air Force has brought Su-27s to Fairford several times, flying displays that include low-level knife-edge passes exploiting the aircraft's exceptional roll rate. A trivia point: the Su-27 was the first production aircraft cleared for sustained operation at angles of attack greater than thirty degrees, a capability that remains impressive even measured against fourth-generation aircraft that followed. Its airbrake — a single large panel that opens from the top of the fuselage behind the cockpit — is among the most visible of any fighter when deployed, rising nearly vertically to slow the aircraft.

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