Blue Ridge-class command ship
The "Blue Ridge" class is the first and only class of amphibious command and control ships to be specifically designed as such from the keel up. The "Blue Ridge" class resulted from almost seven years of planning and construction work. Under the designation SCB-248 (later SCB-400.65), the hull of the Iwo Jima-class amphibious assault ship was used as the basis of the design due to the flight deck's ability to distance antennas to minimize interference between the ships' multiple communications systems and to the deck's ability to act as a ground plane ; the LPH island was replaced with a small centralized superstructure. As designed, the "Blue Ridge" class was capable of supporting the staff of both the Commander of an Amphibious Task Force and the staff of the Commanding General of the Landing Force. The advanced computer system, extensive communications package and modern surveillance and detection systems was molded into the most advanced joint amphibious command and control center constructed at that time. At the time of their commissionings, the ships of the "Blue Ridge" class had the distinction of carrying the world's most sophisticated electronics suites. It was said to  be some thirty percent larger than that of the aircraft carrier , which had been the most complex. They were fitted with a "main battery" of computers, communications gear, and other electronic facilities to fulfill their mission as command ships. An extremely refined communications system was also an integral part of the ships' radical new design. Through an automated patch panel and computer controlled switching matrix her crew could use any combination of communication equipment desired. US Navy long-range communications were heavily reliant on high frequency radio systems in the 1970s and have evolved to predominantly satellite communications in the  2000s. This was illustrated by the long wire antennas, discone antennas, and directional HF yagi or log-periodic antenna initially installed on the class and later removed and replaced with a number of satellite communications antennas. Besides small arms, the "Blue Ridge" class was initially armed with two twin Mark 33 3"/50 caliber guns at commissioning, though they have since been removed. They also carried two Mark 25 launchers and electronics for the Basic Point Defense Missile System (BPDMS) which was added sometime in the 1970s and removed in the 1990s. Two 20 mm Phalanx CIWS systems were added in  the 1980s for point defense. In recent years they have also carried 25 mm Bushmaster cannons. The "Blue Ridge" class consists of two ships. Originally six were requested, three were planned, and only two were built.