The Aérospatiale SA 315B Lama is a French single-engined helicopter. It combines the lighter Aérospatiale Alouette II airframe with Alouette III components and powerplant. The Lama possesses exceptional high altitude performance. The helicopters have been built under licence by Hindustan Aeronautics Limited (HAL) in India, known as the Cheetah; HAL later developed an upgraded variant, powered by the Turbomeca TM 333-2M2 engine, which is known as the Cheetal. An armed version, marketed as the Lancer, was also produced by HAL. It was also built under licence by Helibras in Brazil as the Gavião. The SA 315B Lama was originally designed to meet a Nepalese Army Air Service and Indian Air Force requirement for a rotorcraft capable of undertaking operations at hot and high conditions. Both countries possessed extreme mountain ranges in the form of the Himalayas in which even relatively powerful medium-sized helicopters could not be effectively operated within, thus there was an expressed desire for an aerial vehicle capable of operating in this challenging environment. To achieve the desired performance, Aerospatiale elected to combine elements of two existing popular helicopters in their inventory, the Aérospatiale Alouette II and the Aérospatiale Alouette III to produce a new rotorcraft specialised for high altitude performance. Specifically, the new helicopter, named Lama, was equipped with the Alouette III's Turbomeca Artouste turboshaft powerplant and its dynamic systems, and was furnished with a reinforced version of the Alouette II's airframe. On 17 March 1969, the first SA 315B, powered by an Artouste IIB engine, undertook its maiden flight. On 30 September 1970, the type received its airworthiness certificate, and it was introduced to operational service in July 1971. Due to its favourable high altitude performance, the Lama quickly became popular with operators worldwide, often being deployed within mountainous environments. As with the Alouette series, the type can be fitted for various roles, such as light passenger transport, agricultural tasks, oil-and-gas exploration, aerial firefighting, and other specialised duties. The military variants of the Lama include liaison, observation, photography, air/sea rescue, transport and ambulance duties. The SA315B is particularly suited to mountainous areas due to its performance and can carry underslung loads of up to 1000 kg (2,205 lb). By December 1976, 191 Lamas had been ordered by 68 operators. A large proportion of all SA 315B Lamas to be manufactured were produced under licence in India by Hindustan Aeronautics Limited (HAL), under the name Cheetah. More than three decades after production in India began, HAL was still receiving export orders for the original Cheetah. Along with the Alouette III, the Cheetah was a key product for HAL; experience from manufacturing the type aided in the later development of more advanced indigenous helicopters such as the HAL Dhruv. During the 1990s, HAL developed an armed light attack helicopter based upon the Cheetah, which was given the name Lancer. In 2006, HAL proposed a modernised variant to the Indian Army, designated as Cheetal, the principal change of which was the adoption of a modern, more powerful Turbomeca TM 333-2M2 powerplant in the place of the Artouste; HAL promoting the Cheetal's capabilities for operating in high altitude environments, such as the Siachen Glacier. Other improvements include new warning indicates, a cockpit voice recorder, flight monitoring system, artificial horizon, and modernised electronics. In 2006, an initial 10 Cheetals were ordered by the Indian Air Force. In February 2013, it was announced that the Indian and Nepalese Armies had signed a 300 crore (~US$55 million) contract for the urgent procurement of a further 20 Cheetals. For operational history and 5 variants, click here.