GRIPEN E

GRIPEN E FIGHTER

The Saab JAS 39 Gripen (IPA: [ˈɡrǐːpɛn]; English: griffin)^{[Nb 3][7]} is a light single-engine multirole fighter aircraft manufactured by the Swedish aerospace company Saab. The Gripen has a delta wing and canard configuration with relaxed stability design and fly-by-wire flight controls. It is powered by the Volvo RM12, and has a top speed of Mach 2. Later aircraft are modified for NATO interoperability standards and to undertake air to air refuelling.

In 1979, the Swedish government began development studies for an aircraft capable of fighter, attack, and reconnaissance missions to replace the Saab 35 Draken and 37 Viggen in the Swedish Air Force. A new design from Saab was selected and developed as the JAS 39, first flying in 1988 and entering service with the Swedish Air Force in 1996. Upgraded variants, featuring more advanced avionics and adaptations for longer mission times, began entering service in 2003.

To market the aircraft internationally, Saab formed partnerships and collaborative efforts with overseas aerospace companies, including, in 2001, BAE Systems. On the export market, early models of the Gripen achieved moderate success in sales to nations in Central Europe, South Africa, and Southeast Asia; bribery was suspected in some of these procurements, but authorities closed the investigation in 2009.^[8]

An updated and redeveloped version, designated Gripen JAS 39E/F but also referred to as Gripen NG or Super JAS,^[9] began deliveries to the Swedish and Brazilian air forces as of 2019. The changes include the adoption of a new powerplant, the General Electric F414G, an active electronically scanned array radar, and significantly increased internal fuel capacity.

As of 2020, more than 271 Gripens of all models, A–F, have been built.

Origins

The Gripen is a multirole hfighter aircraft, intended as a lightweight and agile aerial platform with advanced, highly adaptable avionics. It has canard control surfaces that contribute a positive lift force at all speeds, while the generous lift from the delta wing compensates for the rear stabiliser producing negative lift at high speeds, increasing induced drag.^[96] Being intentionally unstable and employing digital fly-by-wire flight controls to maintain stability removes many flight restrictions, improves manoeuvrability, and reduces drag.^[97][98] The Gripen also has good short takeoff performance, being able to maintain a high sink rate and strengthened to withstand the stresses of short landings.^[99] A pair of air brakes are located on the sides of the rear fuselage; the canards also angle downward to act as air brakes and decrease landing distance.^[100] It is capable of flying at a 70–80 degrees angle of attack.^[101]

To enable the Gripen to have a long service life, roughly 50 years, Saab designed it to have low maintenance requirements.^[102] Major systems such as the RM12 engine and PS-05/A radar are modular to reduce operating cost and increase reliability.^[98] The Gripen was designed to be flexible, so that newly developed sensors, computers, and armaments could be integrated as technology advances.^[103] The aircraft was estimated to be roughly 67% sourced from Swedish or European suppliers and 33% from the US.^[104]

One key aspect of the Gripen program that Saab have been keen to emphasise has been technology-transfer agreements and industrial partnerships with export customers.^[105] The Gripen is typically customised to customer requirements, enabling the routine inclusion of local suppliers in the manufacturing and support processes. A number of South African firms provide components and systems – including the communications suite and electronic warfare systems – for the Gripens operated by South African Air Force.^[106] Operators also have access to the Gripen's source code and technical documentation, allowing for upgrades and new equipment to be independently integrated.^[107] Some export customers intend to domestically assemble the Gripen; it has been proposed that Brazilian aerospace manufacturer Embraer may produce Gripens for other export customers as well

Avionics and sensors]

• All of the Gripen's avionics are fully integrated using five MIL-STD-1553B digital data buses, in what is described as "sensor fusion".^[98] The total integration of the avionics makes the Gripen a "programmable" aircraft, allowing software updates to be introduced over time to increase performance and allow for additional operational roles and equipment.^[110] The Ada programming language was adopted for the Gripen, and is used for the primary flight controls on the final prototypes from 1996 onwards and all subsequent production aircraft.^[111] The Gripen's software is continuously being improved to add new capabilities, as compared to the preceding Viggen, which was updated only in an 18-month schedule.^[112]

• Much of the data generated from the onboard sensors and by cockpit activity is digitally recorded throughout the length of an entire mission. This information can be replayed in the cockpit or easily extracted for detailed post-mission analysis using a data transfer unit that can also be used to insert mission data to the aircraft.^[113][114] The Gripen, like the Viggen, was designed to operate as one component of a networked national defence system, which allows for automatic exchange of information in real-time between Gripen aircraft and ground facilities.^[115] According to Saab, the Gripen features "the world's most highly developed data link".^[98] The Gripen's Ternav tactical navigation system combines information from multiple onboard systems such as the air data computer, radar altimeter, and GPS to continuously calculate the Gripen's location.

• The Gripen entered service using the PS-05/A pulse-Doppler X band multi-mode radar, developed by Ericsson and GEC-Marconi, which is based on the latter's advanced Blue Vixen radar for the Sea Harrier that also served as the basis for the Eurofighter's CAPTOR radar.^[117][98] The all-weather radar is capable of locating and identifying targets 120 km (74 mi) away,^[118] and automatically tracking multiple targets in the upper and lower spheres, on the ground and sea or in the air. It can guide several beyond visual range air-to-air missiles to multiple targets simultaneously.^[119] Saab stated the PS-05/A is able to handle all types of air defence, air-to-surface, and reconnaissance missions,^[98] and is developing a Mark 4 upgrade to it.^[120][121] The Mark 4 version has a 150% increase in high-altitude air-to-air detection ranges, detection and tracking of smaller targets at current ranges, 140% improvement in air-to-air mode at low altitude, and full integration of modern weapons such as the AIM-120C-7 AMRAAM, AIM-9X Sidewinder, and MBDA Meteor missiles.^[122]

• The future Gripen E/F will use a new active electronically scanned array (AESA) radar, Raven ES-05, based on the Vixen AESA radar family from Selex ES.^[70] Among other improvements, the new radar is to be capable of scanning over a greatly increased field of view and improved range.^[123] In addition, the new Gripen integrates the Skyward-G Infra-red search and track (IRST) sensor, which is capable of passively detecting thermal emissions from air and ground targets in the aircraft's vicinity.^[124] The sensors of the Gripen E are claimed to be able to detect low radar cross-section (RCS) targets at beyond visual range.^[125] Targets are tracked by a "best sensor dominates" system, either by onboard sensors or through the Transmitter Auxiliary Unit (TAU) data link function of the radar.