armed variants of the Boeing-Vertol ACH-47A, Kaman HH-2C Tomahawk, Piasecki 16H Pathfinder, Sikorsky S-61, and the Bell 209. During April 1966, Bell's submission emerged victorious in an evaluation against the other rival helicopters. The US Army promptly signed the first production contract, ordering an initial batch of 110 aircraft. By the end of the year, rapid follow-on orders had increased this to 500 Cobras. Bell added "Cobra" to the UH-1's Huey nickname to produce its HueyCobra name for the 209. The Army applied the Cobra name to its AH-1G designation for the helicopter. The Bell 209 demonstrator was used for the next six years to test weapons and fit of equipment. An additional use for the demonstrator was participating in marketing initiatives. It was also modified to match the AH-1 production standard by the early 1970s. The demonstrator was retired to the Patton Museum at Fort Knox, Kentucky and converted to approximately its original appearance. Into production The Bell 209 design was modified in several respects for production. The retractable skids were replaced by simpler fixed skids; this was not due to any recorded design flaw or serviceably, but it was feared that the landing gear bay could become inundated with mud. Furthermore, a new wide-chord rotor blade was adopted. It was also decided that a plexiglass canopy should replace the Model 209's armored glass canopy, which was heavy enough to negatively impact performance. The umbrella-shaped dive brake was deleted, having reportedly self-destructed during its first test flight. Numerous changes of the design were incorporated after the Cobra had entered service. The principal amongst these changes was the repositioning of the tail rotor from the helicopter's left side to the right, which facilitated an increase in the effectiveness of the tail rotor. The AH-1 was the first U.S. Army helicopter not named for a Native American people since the practice began with the H-13 Sioux and continued with the UH-1 Iroquois, AH-56 Cheyenne, OH-58 Kiowa, and later helicopters. Within its first decade of service, the US Army had put the original Cobra model through various exercises and operations, which highlighted both the attack helicopter's promise and areas in which it could be improved. By 1972, the US Army openly sought an improved anti-armor capability. Under the Improved Cobra Armament Program (ICAP), trials of eight AH-1s fitted with TOW missiles were conducted in October 1973. After passing qualification tests the following