Su-27 Flanker

The aircraft is equipped to operate autonomously in combat over hostile territory, in escort of deep-penetration strike aircraft and in the suppression of enemy airfields. The aircraft provides general air defence in cooperation with ground and airborne control stations. A naval variant with folding wings, the Su-33, exists.

The Su-27 (Nato designation Flanker) is the front-line fighter aircraft designed by the Sukhoi Design Bureau and manufactured by Irkut Corporation. The export version is the Su-27SK.

Su-27 Flanker development

Su-27 entered production in 1982 and is in service with Russia, Ukraine, Belarus, Kazakhstan, Indonesia, Uzbekistan and Vietnam, and is built under license in China as the F-11. A variant, the Su-30MK, has been sold to India with licensed local production.

50 aircraft were ordered from Irkut and the first entered service with the Indian Air Force in September 2002. The last was delivered in December 2004.

The first of up to 140 aircraft indigenously built by Hindustan Aeronautics Ltd (HAL) was delivered in November 2004. China ordered 76 two-seat Su-30MKK and 24 Su-30MK2 naval fighters. Deliveries were completed in August 2004. Indonesia ordered two Su-27SK and two Su-30MK aircraft which were delivered in September 2003.

In May 2006, the Su-27 was selected by the Mexican Navy. Ten aircraft are required, eight single-seat and two Su-27UB two-seat trainers.

In August 2007, Indonesia ordered a further three Su-27SKM and three Su-30MK2 aircraft.

The latest version is the Su-27SM, an upgrade for the Russian Air Force which has strengthened fuselage for extra weapons payload, improved N001 radar, glass cockpit with three-colour multi-function displays and improved avionics. The first was delivered in December 2003.

Su-27 Design

The Su-27 is a highly integrated twin-finned aircraft. The airframe is constructed of titanium and high-strength aluminium alloys. The engine nacelles are fitted with trouser fairings to provide a continuous streamlined profile between the nacelles and the tail beams. The fins and horizontal tail consoles are attached to tail beams.

The central beam section between the engine nacelles consists of the equipment compartment, fuel tank and the brake parachute container. The fuselage head is of semi-monocoque construction and includes the cockpit, radar compartments and the avionics bay.

Weapons

The aircraft is equipped with a 30mm GSh-301 gun with 150 rounds of ammunition and a range of missiles, rockets and bombs mounted externally on ten hardpoints.

The aircraft's infrared search and track system, laser rangefinder, radar and helmet-mounted target designator provide detection, tracking and attack capability.

The range of air-to-air missiles carried by the Su-27 aircraft includes: R-27R1 (Nato designation AA-10A Alamo-A), all-aspect medium-range missile with semi-active radar homing and R-27T1 (AA-10B Alamo-B) with infrared homing and a range from 500m to 60km; and R-73E (AA-11 Archer) all-aspect, close-combat air-to-air missile with infrared homing and a range from 300m to 20km.

Ordnance for air-to-ground missions include: 100kg, 250kg and 500kg freefall and retarded aerial bombs; 500kg incendiary devices; 25kg and 500kg RBK cluster bombs; and C-8, C-13 and C-25 unguided aerial missiles.

Countermeasures

The Su-27 is equipped with a new electronic countermeasures suite for individual aircraft, and for mutual and group protection in the forward and rear hemispheres.

The countermeasures system includes a pilot illumination radar warning receiver, chaff and infrared decoy dispensers, and an active multi-mode jammer located in the wingtip pods.

Sensors

The Su-27 is equipped with a Phazotron N001 Zhuk coherent pulse Doppler radar with track-while-scan and look-down / shoot-down capability.

The range of the radar against 3m² targets is over 100km in the forward hemisphere and 40km in the rear hemisphere. The radar has the capacity to search, detect and track up to ten targets with automatic threat assessment and proritisation.

The aircraft has an OEPS-27 electro-optic system, which includes an infrared search-and-track (IRST) sensor collimated with a laser rangefinder. The range of the electro-optical system is 40-100km, depending on the aspect angle presented by the target.

Communications

The radio communications suite provides: voice and data; VHF/UHF radio communications between aircraft and ground control stations within sight range; voice radio communication with ground control stations and between aircraft up to a range of 1,500km; an encrypted data link for combat information exchange between aircraft; and command guidance from ground control stations using automatic interception mode.

Systems

The Su-27 is equipped with an electro-optical fire-control system, supplied by the Urals Optical and Mechanical Plant (YOM3), and a Geofizika FLIR (forward-looking infrared) pod. Leninetz of St Petersburg supplies the radar systems and TsNIRTI the electronic countermeasures suite.

Engines

The Su-27SK is powered by two AL-31F turbofan engines, designed by the Lyulka Engine Design Bureau (NPO Saturn). Each engine has two air intakes: a primary wedge intake and a louvred auxiliary air intake.

The twin-shaft, turbo-fan engine has after-turbine flow mixing, a common afterburner, an all-mode variable area jet exhaust nozzle, an independent start and a main electronic control, and a reserve hydromechanical engine mode control system. The high-temperature sections of the engines are made of titanium alloy.

An Su-27 fitted with AL-41F1 engines being developed by NPO Saturn took its first flight in March 2004. The uprated engine provides a thrust of 145kN (33,000lb).