Rooivalk celebrates its thirtieth birthday
By Willie Bodenstein
Faced with the increasingly conventional nature of the South African Border War during the 1980's, the South African Defence Force recognised the need for a dedicated attack helicopter. The Rooivalk project began in early 1984 under the auspices of the Atlas Aircraft Corporation, a predecessor of Denel Aviation.
Due to the great difficulty posed by the prospects of designing and manufacturing a clean-design helicopter, which would have substantially increased the cost and timescale of the project, it was decided to base the attack helicopter upon an existing design. At the time, the SAAF operated two principal helicopter types the Aérospatiale Alouette III and the Aérospatiale SA 330 Puma.
The Atlas XH-1 Alpha, development of which started in early 1980, was the first prototype to emerge from the program. The XH-1 (Experimental Helicopter One) was developed from an Alouette III airframe, retaining that helicopter's engine and dynamic components. Modifications included the replacement of the original cockpit with a stepped tandem one, the addition of a 20 mm cannon on the nose and the conversion of the undercarriage to a tail-dragger configuration. On 3 February 1985, the XH-1 conducted its maiden flight. The results of flight tests of the XH-1 were ultimately good enough to convince both Atlas and the SAAF that the concept was feasible, opening the door to proceed with the development of the Rooivalk.
The other helicopter operated by the SAAF was the Puma that was substantially larger and was equipped with more powerful engines than the Alouette III and which provided a broader basis as a development platform for the attack helicopter. Another key factor for its selection was the parallel development of a localised and improvement model of the Puma in South Africa, known as the Atlas Oryx. The Oryx possessed an increased power-to-weight ratio and had improved performance in the high temperature climate that the type was typically being operated in.
Rooivalk has been designed to operate for prolonged periods without sophisticated support. All that is needed to keep it operational is a medium transport helicopter equipped with a basic spare supply plus four ground crew.
Three prototypes were constructed, the first being the XDM for basic platform testing which first flew on 11 February 1990. This was followed by the ADM version which included advanced avionics and weapons that flew in 1992. The final version was the EDM that flew in 1999 and which included all lessons learned.
The design philosophy behind Rooivalk is quite simply not to be seen and if seen, not be hit, if hit to be able to sustain flight and if not able to sustain flight to survive the crash.
Rooivalk's small frontal area with parallel and near flat cockpit glazing, nap of the earth flying capabilities (NOE), camouflage designed by the CSIR and bad weather and night flying capabilities, shielded compressor faces and unique engine exhausts suppressors makes it a rather difficult target to see and acquire. If seen, its electronic counter measures, agility and maneuverability, standoff weapons and high excess power in hot and high conditions make it an elusive target to hit. If hit, its 12.7 mm API ballistic tolerance, wide spacing of the engines, dual redundancy systems, fire protection system and dry run gearbox capability makes it a difficult target to down. If downed, its over designed undercarriage, single engine capability, survivable sink rate of 10.5 meters per second, crash sensor and coupling in the electrical and fuel systems, shock absorbing seats as well as the placement of the engines ensures the safety and chances of survival of the crew.
Rooivalk seats two with the pilot occupying the rear cockpit and the navigator/ weapons systems officer (WSO) in the front. It can however be flown from either cockpit and in most cases the WSO will also be a pilot. More or less the same size as the Oryx Rooivalk, it has a maximum take-off weight of 8450 kg, never to exceed speed (Vne) of 167 kts (309 km/h), cruise at 120 kts (216 Km/h) and has a range without ferry tanks of approximately 600 km and with ferry tanks of 1,100 km. Armament will depend on the type of mission and can include, besides the look and shoot chin mounted 20 mm canon, a cluster of nineteen 70 mm standoff rockets with a range of 6 Km per launcher, two per stub wing as well as fire and forget heat seeking air-to-air missiles and anti armour air to ground long range missiles.
On the world stage, Rooivalk has won critical acclaim for itself and South Alicia's aerospace industry. Its performance and level of integrated technology have pushed the helicopter into a league with its rivals, the McDonnell Douglas Apache and Eurocopter Tiger.
South African forces are currently deployed in United Nations peace keeping missions to various hot spots on the African continent, where in the past, they relied on their foreign counterparts that were mostly not suitably equipped for assistance and reinforcement when already volatile situations get out of hand. The deployment of Rooivalk has been a game changer and South Africa's own has already proved its mettle in a number of engagements that, was it not for its presence, might have resulted in the loss of life of our soldiers on the ground.
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