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Atlas Cheetah
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).
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.
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