Atlas Cheetah

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AtlasCheetahC.jpg

Atlas Cheetah C

The Atlas Cheetah is a fighter aircraft of the South African Air Force. It is a major upgrade of the Dassault Mirage III. Three different variants were created, the dual-seat Cheetah D, and the single-seat Cheetah E and Cheetah C. The Cheetah E was retired in 1992, and the SAAF currently has a mixture of 28 Cheetah Cs and Cheetah Ds in operational service. Commencing from 2007, the Cheetah fleet will be replaced by 28 Saab JAS-39 Gripens (19C/9D).

Contents

1 Development

2 Operational history

3 Variants

3.1 Cheetah C
3.2 Cheetah D
3.3 Cheetah E
3.4 Cheetah R

4 Specifications (Cheetah C)

4.1 General characteristics
4.2 Performance
4.3 Armament

5 References and external links

6 Related content

Development

The Atlas Cheetah programme grew out of South Africa's requirement for a modern fighter and strike aircraft in the 1980s, due to the need for more advanced aircraft to attain an edge over the ever more sophisticated Soviet aircraft being supplied to Angolan and Cuban forces in action against South African forces in the Border War, and the increasing cost of maintenance due to the age of the aircraft used by SAAF. The United Nations Arms Embargo in place from at the time prevented South Africa from purchasing new aircraft from other countries, thus making an upgrade of existing aircraft the only option. By this stage, the South African aviation industry had reached the level of technical capability to make a large and sophisticated upgrade possible, leading the SAAF to make the only possible decision, to radically upgrade one of the existing types in service.

At the time the SAAF's fast jet fleet consisted of Dassault Mirage III (EZ/CZ/BZ/DZ/D2Z/RZ/R2Z) aircraft and Mirage F1 (AZ/CZ) aircraft. Though the Mirage F1s were the most modern of the fleet, having been delivered from 1977 onwards, they were the primary element of South Africa's air defence and strike fleet and to withdraw them for an upgrade would have left an unacceptable gap in its air defence and strike capability. In addition there were already a few successful Mirage III upgrades from which to learn, such as the Kfir and Mirage III NG, so the SAAF's Mirage III fleet was chosen as the basis for the upgrade.

The upgrade was carried out by Atlas Aviation (formerly Atlas Aviation Corporation and latterly Denel Aviation), and consisted of a complete refurbishment of the airframe down to zero hours (in which some 50% of the original airframe is said to have been replaced), the fitment of non-moving canards (slightly different to those on the Kfir) just aft of the engine intakes, two new stores pylons at the wing roots, an aerial refuelling probe, new ejection seats, a more powerful engine, the Atar 9K50 (upgraded in South Africa), in the D and C variants, a new main wing spar along with a new "drooping" leading edge and a dog-tooth incision on each wing, modern elevons controlled by a twin computer flight control system, and strakes on the nose to improve the Cheetah's high-Angle_of_attack (AoA) performance. The aerodynamic refinements alone increased the turn rate by 15%, increased the AoA, reduced the minumum airspeed to 100kts and increased maximum take-off weight by 700kg. However, it also resulted in a 5% decrease in maximum level speed and acceleration.

In addition, a highly sophisticated avionics, radar, EW and self-protection suite was installed, necessitating a lengthening of the nose. This entailed the fitment of an EW suite which includes missile and radar warning sensors, and automatically engages the aircraft's self-protection system, which consists of electronic jammers and chaff/flare dispensers; the integration of a South African helmet-mounted sight and an oversized Head-Up Display (HUD); the installation of an advanced Pulse-Doppler radar and sophisticated cockpit instrumentation.

It has been alleged that some Israeli assistance was involved in the Cheetah programme, something the SAAF will neither confirm nor deny. However, considering the close ties between South Africa and Israel at the time, especially in the sphere of military research, it can be assumed that at least some of the components were sourced from Israel. There is no available evidence of direct Israeli assistance in the upgrade itself, but international experts in aviation often draw conclusions based on the close political ties between the two countries during the years of their mutual ostracism. Also, the virtually identical aerodynamic refinements (even down to shared canard geometries) of both Cheetah and Kfir strongly re-enforce this view, as does the puported fitment to some Kfir's of the Armscor/Denel's extremely compact and simple off-bore helmet mounted missile-aiming system.

16 of the SAAF's 27 Mirage IIIDZ/D2Z aircraft were converted to Cheetah D standard, 16 of its Mirage IIIEZ aircraft were converted to Cheetah E standard, but no South African Mirage airframes were used for the 38 Cheetah Cs. It has recently been confirmed that the source for these airframes was Israel, which supplied Mirage III airframes

Operational history

First to roll off the production line were the Cheetah Ds and Cheetah Es, though it appears the Cheetah Ds had production priority. The first aircraft to be converted was a Mirage IIID2Z, no.845, which arrived at Atlas in April 1983. The date of completion is unknown, but the first Cheetah D was officially unveiled on 16 July 1986, by which time a number of Cheetah Ds had already entered service with 89 Combat Flying School at AFB Pietersburg, though the type was only declared operational in 1987. The second and third aircraft to be delivered to Atlas were both Mirage IIIEZs, and the resulting Cheetah Es went into service with 5 Squadron at AFB Louis Trichardt. 16 of each type were in service by 1991 when the Cheetah D and E conversion lines closed, by which time the first of the 38 Cheetah Cs were being converted, with the first being rolled out in January 1993. All the Cheetah Cs entered service with 2 Squadron, also at AFB Louis Trichardt. None of the Cheetah variants ever saw combat in the Border War, but the Cheetah Es were used as permanent interceptor standby aircraft, with a minimum of two aircraft on round the clock alert status, until the end of the Border War in 1989.

With the entering into service of the Cheetah C, the Cheetah Es were withdrawn from service and 5 Squadron was disbanded in 1992. Soon afterwards, 89 Combat Flying School was also disbanded, and all the Cheetah Ds were transferred to 2 Squadron, where they remain today.

Variants

Cheetah C

A Cheetah C in flight

The Cheetah C is the ultimate development of the Cheetah series, and it is currently the only fighter-aircraft type in service with the SAAF. Many of the features of this aircraft are still classified, and the SAAF is unwilling to reveal too many details. What is known is that in addition to the upgrades described above, the Cheetah C incorporates a more sophisticated avionics and navigation suite and a new pulse-doppler, multi-mode radar, both of which are regarded as being better than the systems fitted to Block 50 F-16s, and one of the most advanced EW systems ever fitted to a fighter aircraft. The aircraft is also fitted with a datalink, though the capabilities of this system are unknown, and it received updated versions of the helmet-mounted sight, HUD and improved HOTAS controls.
Other improvements include the fitment of a single-piece wrap-around windshield with an anti-radiation coating in place of the old three-piece version, a new in-flight refuelling probe with less external piping, new undercarriage and suspension, the deletion of the wing fences, an upgraded version of the Atar 9K50 and a new nose to incorporate the more sophisticated electronics and radar.
Like the Cheetah D, the Cheetah C is capable of delivering Precision-Guided Munitions (PGMs), ranging from Laser-Guided Bombs (LGBs), to GPS-guided weapons and TV-guided bombs. It also has the capability of using stand-off air-to-ground weapons such as the MUPSOW and TORGOS. In addition, it's able to carry a raft of air-to-air weapons, and the SAAF currently equips its aircraft with the V4 R-Darter, a Beyond Visual Range (BVR) radar-guided missile, and the U/Darter, a highly-capable short-range Infra-Red (IR)-guided missile.

A measure of the capabilities of the Cheetah C is the result of an Air-combat maneuvering (ACM) exercise between the Cheetah Cs of 2 Squadron and F-15E Strike Eagles of the 494th Fighter Squadron, USAF at RAF Lakenheath, after which the score tallies for each side were almost exactly equal.

The Cheetah C will remain in SAAF service until 2012, when the last examples will be replaced by the JAS-39C Gripen.

Cheetah D

The Cheetah D was the sole two-seater variant, and is mainly used operationally as a training aircraft for pilots converting to the Cheetah C, though does have a secondary attack capability, including the ability to deliver Precision-guided munitions (PGMs). All Cheetah Ds are fitted with the Atar 9K50, and at the present time the entire fleet is undergoing a significant upgrade of the engine under the code-name Project Recipient. Recently, the Cheetah D's avionics were also upgraded, to bring them on par with the avionics in the Cheetah C.
Cheetah D No.845 is currently based at the Test Flight and Development Centre (TFDC) as a systems testing aircraft. It was recently used in the development of the Denel Dynamics MUPSOW stand-off weapon. Denel also keeps two Cheetah Ds for testing, No.844 and No.847. The former is Denel's standard systems testing aircraft, while the latter was used in the evaluation of the SMR-95 engine, a development of the Klimov RD-33. The performance increase offered by the Russian engine was impressive, but budget cuts and problems with the aircraft's centre of gravity ended the program. No.847 is currently in storage with Denel.

These aircraft will be replaced by the JAS-39D Gripen from 2007 onwards.

Cheetah E

The single-seater Cheetah E is regarded by most observers as having just been an interim fighter for use in the period before the Cheetah Cs became operational, due to the very short operational life of the Cheetah E, which was only a few years from its entry into operational service in 1987/88 to its retirement in 1992.
It was fitted with a comparatively simple avionics suite and radar, and retained the Atar 9C-3 engine. Its typical mission while in service was as a standby interceptor, whereby a minimum of two aircraft, armed with two V3B (later V3C) missiles, would be on permanent alert status in case of an attack from the north.

All the aircraft were placed into storage, though the final example, No.842, was painted in a non-standard camouflage scheme and used for systems testing. No.842 is currently with the SAAF Museum, and is stored at AFB Swartkop. In 2003, Chile purchased five of the mothballed aircraft, numbers 819, 820, 827, 832 and 833. The country has also indicated its desire to purchase seven more aircraft (numbers 822, 823, 825, 828, 829, 831 and 834), subject to the agreement of a suitable purchase price. The Chilean Air Force (FAC) will use the Cheetah E airframes as a source of spares for its similar Pantera aircraft.

Cheetah R

The Cheetah R was a feasibility study into an extension of the Cheetah upgrade programme to include a specialist reconnaissance model. An Atar 9K50-engine Mirage IIIR2Z, No.855, was chosen as the basis for the upgrade. In addition to the airframe refurbishment, No.855 received a new nose design and the same radar as used in the Cheetah E, the twin DEFA 30mm cannons were removed and it was the only Cheetah type to not receive an in-flight refuelling probe.
The SAAF decided not to proceed with the Cheetah R programme, and so No.855 was fitted with the Atlas Advanced Combat Wing (ACW), for which it was used as a testing and development aircraft. No.855 was eventually scrapped, and its ACW put in storage at the SAAF Museum.

Instead of having a dedicated reconnaissance aircraft, the SAAF uses the Vinten Vicon 18 Series 601 reconnaissance pod on the Cheetah C.

Specifications (Cheetah C)

General characteristics

Crew: One
Length: 15.55 m (40.19 ft)
Wingspan: 8.22 m (34.78 ft)
Height: 4.50 m (13.94 ft)
Wing area: 35 m² (380 ft²)
Empty: 6,600 kg (14,600 lb)
Loaded: kg ( lb)
Maximum takeoff:13,700 kg (30,200 lb)
Powerplant: 1x Snecma Atar 9K50, 7,200 kgf (71 kN, 15,900 lbf) thrust turbojet

Performance

Maximum speed: Mach 2.2
Combat Radius: km ( miles)
Service ceiling: m ( ft)
Rate of climb: 1,494 m/min (4,900 ft/min)
Wing loading: 250 kg/m² (52 lb/ft²)
Thrust/Weight: 15,873 lb (70.6 kN) with Afterburner

Armament

Guns: 2x 30 mm DEFA cannons
Bombs: 250kg Laser-guided bombs (LGB), GPS-guided bombs, 250kg 'booster' bombs, various unguided 'iron' bombs
Missiles: V4 R-Darter (BVR missile), U/Darter, V3C Darter, Python 3
Other: Two auxiliary fuel tanks (fitted with two 125kg bomb pylons each)

References and external links

Material used with kind permission from IPMS SA - the site contains a detailed account of the Cheetah with a large number of photo references. http://www.ipmssa.za.org/