So effective was the Leader concept, that a number of Cygnus class command couriers were rearmed and modified to act as Leaders to supplement the insufficient numbers of Detroyats and Apaches. Destroyer groups led by Apaches served with distinction throughout the Four Years War, and a group led by the USS Tartar was instrumental in the Attack of Convoy Y-16Z in 2253, the first significant Federation fleet victory of the war. In service the Apache proved to be as dependable as its illustrious ancestor. It was intended that the Apache would be allocated to Destroyer groups allocated to more remote areas, and as a result the secondary hull was enlarged to enable it to carry spares and supplies to support its assigned group. During the design process the class evolved, the saucer was modified to feature an elongated rear edge and the secondary hull was massively enlarged compared to that of the Detroyat. The design, later to be named Apache, started off as a modified Detroyat design.

The Heavy Destroyer would act as the command ship for the group, and also provide long range sensors. The total of 36 Heavy Destroyers was felt to be sufficient to allocate one to each group of 6 standard destroyers operating along the Klingon and Romulan borders. As a result the 10 Detroyat class ships were refitted with modern warp drives, and with the new sensor systems, it was also decided to order 26 vessels to supplement the Detroyats. New sensor technology, such as that fitted to the Constitution class offered massive range improvements, but it was felt that the sensor suite and associated systems were too large to be fitted to standard Destroyers. In 2243, Starfleet Tactical suggested the development of a new tactic for Destroyer operations, the use of leaders. Historically, Starfleet had only ever fielded one heavy Destroyer class, the Detroyat class of 2224.

Star trek belknap class