High Quality Content by WIKIPEDIA articles! The Australian light destroyer project aimed to build a class of small destroyers for the Royal Australian Navy (RAN). The project began in 1966 with the goal of developing simple light destroyers (DDL) to support patrol boat operations. The project was rescoped in 1969 when the Navy decided to use the ships to replace other destroyers as they retired, leading to an increase in the design`s size and complexity. Concerns over the ships` cost and technological risk led the government to cancel the DDL project in 1973 on the RAN`s advice, and a variant of the United States` Oliver Hazard Perry class frigate was procured instead.