to enable coloured smoke to be emitted during displays, but essentially these airframes can still perform their pilot training function. Combat use of trainers In smaller air forces basic trainers, in addition to being used for training, are used to provide air support in the counter-insurgency and airborne forward air control role. Most advanced trainers are capable of carrying and delivering war loads. However, most of these aircraft do not have the counter measures and sensors required to survive alone in a modern high intensity war fighting scenario, for example being vulnerable to MANPADS. However, they may still have a war fighting role in low intensity theatres if operated in conjunction with more capable aircraft. Historically many jet trainers were marketed with specialised attack variants e.g. the BAC Jet Provost/BAC Strikemaster and the Cessna T-37 Tweet/A-37 Dragonfly. Especially against opponents operating without a fighter screen or an effective anti-aircraft capability, such trainer derived attack aircraft could perform adequately. For example, Impala aircraft derived from the Aermacchi MB-326 trainer formed the main strike strength of the South African Air Force in its Bush war, and aircraft such as the Hongdu JL-8 are being acquired for the attack role in low intensity theatres. Despite their vulnerability, even small numbers of weapons-carrying trainer aircraft may achieve a disproportionate effect due to the element of surprise, especially when the attacked side believes to hold air supremacy. Forces that have used light trainer aircraft to great effect include the Biafran use of MFI-9s and the Liberation Tigers of Tamil Eelam use of covertly acquired light aircraft. In high-intensity conflicts, advanced trainer type aircraft can have a military utility if they operate under an umbrella of other aerial assets. For example, the Franco-German Dassault/Dornier Alpha Jet had an anti-shipping and light strike role when operating under an air umbrella provided by fighter aircraft, while the RAF planned to use pairs of gun- and AIM-9 Sidewinder-armed Hawk trainers in the point defence role. Each pair of Hawks was to be teamed with a Phantom FGR.2, in effect using the Phantoms as an Airborne Early Warning and Control system. Although never tested it was believed that the Hawk, combined with AIM-9L and flown by some of the best pilots in the RAF including those from the Red Arrows, would have made a viable air defence fighter. The future As the capabilities of front-line aircraft have increased, this has