developed, such as the twin engined AH-1 SeaCobra/SuperCobra and the experimental Bell 309 KingCobra. Furthermore, surplus AH-1 helicopters have been reused for other purposes, including civilian ones; numerous examples have been converted to perform aerial firefighting operations. Development Background Closely related to the development of the Bell AH-1 is the story of the Bell UH-1 Iroquois transport helicopter—an icon of the Vietnam War and one of the most numerous helicopter types built. The UH-1 made the theory of air cavalry practical, as the new tactics called for US forces to be highly mobile across a wide area. Unlike before, they would not stand and fight long battles, and they would not stay and hold positions. Instead, the plan was that the troops carried by fleets of UH-1 "Hueys" would range across the country, to fight the enemy at times and places of their own choice. The massive expansion of American military presence in Vietnam opened a new era of war from the air. The linchpin of US Army tactics was the helicopters, and the protection of those helicopters became a vital role. It became clear that unarmed troop helicopters were vulnerable against ground fire from Viet Cong and North Vietnamese troops, particularly as they approached landing zones to disembark or embark troops. Without friendly support from artillery or ground forces, the only way to pacify a landing zone was from the air, preferably with an aircraft that could closely escort the transport helicopters, and loiter over the landing zone as the battle progressed. By 1962, a small number of armed UH-1As were used as escorts, armed with multiple machine guns and rocket mounts. However, these makeshift gunships came with considerable tradeoffs, particularly being barely able to keep up with the troop transports they were intended to protect. While some officials within the Pentagon, particularly those within the US Army, had recognised the potential value of purpose-built armed rotary aircraft as early as 1962 and were keen to see such a vehicle developed promptly, the issue was complicated in part due to inter-service politics. The United States Air Force (USAF) largely held the opinion that most forms of US military aircraft should be operated only by their service, and that the US Army would be intruding into their domain by developing a complex armed aerial combatant, and ought to be largely restricted to transport aircraft. Meanwhile, some Army officials were concerned