Bell XHSL-1

In 1950, the U.S. Navy launched a competition for a new helicopter to be designed specifically for the Anti-Submarine Warfare role as the existing helicopter inventory could not accomplished the ASW mission. Bell proposed its first and only tandem-rotors design, the Model 61, and won the competition. A contract was signed for three prototypes which were designated XHSL-1. First flight was made in 1953. Performance in the air was judged acceptable, so 78 production helicopters were ordered by the U.S. Navy and Britain Fleet Air Arm. In 1955, the first carrier trials were made and it was found the HSL-1 suffered high noise levels that limited the sonar operator's ability to identify contacts. The noise problem led to a production cut, the cancellation of the follow-on order and the Navy ordered the Sikorsky HSS-1 instead. The remaining helicopters were used for mine-sweeping, training or as spares until the end of 1960. None of them were equipped and used operationally for ASW.