fuel that was most common and easily obtained at the time of the program. Fuels commonly used by those participating in the user program included diesel and home heating oil. More than 1 million miles (1.6 million km) were accumulated in testing by the 50 cars given to the public, which were driven by 203 users before the program ended in January 1966. The users lived in 133 cities in the 48 contiguous states and Washington, D.C.; 180 were male and 23 were female, their ages ranged from 21 to 70, and 60% were Chrysler owners. Legacy In April 1966, product planning and development vice president Harry E. Chesebrough noted that the 50 test cars would be taken off the road regardless of whether the Chrysler Turbine Car went into production. Chrysler destroyed 46 of the cars after it finished the user program and other public displays. Forty-five of the cars were burned and crushed at a scrapyard south of Detroit, and the other was destroyed at Chrysler's Chelsea Proving Grounds. A widely circulated explanation was that the cars were destroyed to avoid a substantial tariff on the imported Ghia bodies, although author Steve Lehto claims that this idea has been "largely discredited". The destruction of the cars was in line with the automobile industry's practice of not selling non-production or prototype cars to the public. According to Lehto, the decision was influenced by Chrysler's public relations concerns: the potential difficulty of keeping the cars running and fears that owners would replace the turbine powerplants with piston engines. A Chrysler executive was quoted in Look: "Our main objective is research, and we did not want turbines turning up on used-car lots." A similar practice was later used by General Motors with its EV1 when it terminated the program and destroyed most of the cars in 2003. Chrysler's development of turbine engines continued from the late 1960s into the 1970s, resulting in the creation of fifth- and sixth-generation engines. The turbines ultimately failed to meet government emissions regulations and had relatively poor fuel economy, despite promising early results and a $6.4 million contract from the Environmental Protection Agency. According to Charles K. Hyde, the company's effort to enlarge and diversify its turbine program was unsuccessful and spread its "already-thin executive talent pool even thinner". An October 1967 Department of Commerce report concluded that the turbine engine was "unsuited to automobiles". Development