in the destruction of the tank. Using RPGs as improvised anti-aircraft batteries has proved successful in Somalia, Afghanistan and Chechnya. Helicopters are typically ambushed as they land, take off or hover. In Afghanistan, the Mujahideen often modified RPGs for use against Soviet helicopters by adding a curved pipe to the rear of the launcher tube, which diverted the backblast, allowing the RPG to be fired upward at aircraft from a prone position. This made the operator less visible prior to firing and decreased the risk of injury from hot exhaust gases. The Mujahideen also utilized the 4.5-second timer on RPG rounds to make the weapon function as part of a flak battery, using multiple launchers to increase hit probabilities. At the time, Soviet helicopters countered the threat from RPGs at landing zones by first clearing them with anti-personnel saturation fire. The Soviets also varied the number of accompanying helicopters (two or three) in an effort to upset Afghan force estimations and preparation. In response, the Mujahideen prepared dug-in firing positions with top cover, and again, Soviet forces altered their tactics by using air-dropped thermobaric fuel-air bombs on such landing zones. As the U.S.-supplied Stinger surface-to-air missiles became available to them, the Afghans abandoned RPG attacks as the smart missiles proved especially efficient in the destruction of unarmed Soviet transport helicopters, such as Mil Mi-17. In Somalia, both of the UH-60 Black Hawk helicopters lost by U.S. forces during the Battle of Mogadishu in 1993 were downed by RPG-7s. Molotov cocktail The Molotov cocktail is a generic name used for a variety of improvised incendiary weapons. Due to the relative ease of production, they are frequently used by amateur protesters and non-professionally equipped fighters in urban guerrilla warfares. They are primarily intended to set targets ablaze rather than instantly destroy them. A Molotov cocktail is a breakable glass bottle containing a flammable substance such as gasoline/petrol or a napalm-like mixture, with some motor oil added, and usually a source of ignition such as a burning cloth wick held in place by the bottle's stopper. The wick is usually soaked in alcohol or kerosene, rather than gasoline. Improvised artillery Improvised and homemade mortars, howitzers and rocket launchers have been used by insurgent groups to attack fortified military installations or to terrorize civilians. They are usually constructed by in a variety of different ways, for example, from heavy steel piping mounted on a