U. S. Navy ships continued to change with even greater momentum, ushering in another new era—that of nuclear propulsion, jet power, rockets, and guided missiles. New types of ships    have emerged—ships such  as  guided-missile  cruisers,  tactical  command ships, and helicopter flattops. The era of the 50s, 60s, 70s, 80s, and on into the 90s has seen the emergence of the nuclear Navy. The  heart  of  today’s  nuclear  fleet  is  a  highly complicated unit known as the nuclear reactor, which offers the following advantages: Almost unlimited steaming endurance at high speed. Nuclear ships have increased flexibility; an ability to obtain ammunition, aviation fuel, and  other  supplies  from  remote  places  in  a minimum amount of time; and an attack ability in a much greater area. Reduced vulnerability. Nuclear ships need not remain exposed as long as nonnuclear vessels during  replenishment.  They  can  maneuver  to avoid attack. Reduced  dependence  on  logistic  support. Nuclear  ships  require  fewer  mobile  support forces. Greater attack effectiveness. Nuclear ships can remain in battle areas for a greater length of time and have a greater ability to exploit weather conditions to their advantage. Elimination of huge funnels. That provides more room for such items as a big, powerful radar. Power  available  upon  command.  Nuclear reactors  eliminate  the  need  to  order  “more boilers on the line” a half hour before full power is  desired.  Heat  is  produced  in  the  nuclear reactor; in turn, steam and power is produced with little delay. Reduction from full power to one-third or stop is equally responsive. Reduced maintenance. The absence of corrosive stack gases cuts down on the wear and tear of the ships and a lot of at-sea and in-port repairs. The Navy has been advancing in other areas of the surface fleet as well. An example is the new amphibious assault ships (LHAs). The LHAs are the largest and fastest amphibious ships in the Navy inventory and offer the  greatest  operational  versatility  in  the  history  of amphibious warfare. The size of the LHAs alone is impressive. The first of the LHAs, the USS Tarawa, is 820 feet long and 106 feet wide. The high point of its mast is 221 feet above the keel, and it has a full displacement of 39,300 tons. It can carry a large landing force with all its equipment and supplies, landing them either by helo or amphibious craft  or  both.  The  primary  advantage  of  these g e n e r a l - p u r p o s e a s s a u l t s h i p s i s t a c t i c a l integrity—getting a balanced force to the same point at the same time. Spruance-class ships are the Navy’s prime ASW destroyers.  They  are  fitted  with  our  most  powerful sonar, helicopters, our best ASW weapons, and the Harpoon surface-to-surface missile system. The most recent additions to the surface fleet are the Ticonderoga-class cruisers and the Arleigh Burke-class destroyers. Both are powered by gas turbines and are capable of high-speed transits. They are also outfitted with  the  Navy’s  new  Aegis  weapons  system.  That system has the capability to track and engage multiple targets, using a complex system of radars, missiles, guns,  torpedoes,  and  self-defense  systems.  These capabilities make these cruisers and destroyers the most survivable units of today’s surface fleet. Our ability to quickly deploy large carrier battle groups and surface action groups quickly will assure our allies of our ability to exercise sea control. That ability, coupled  with  the  U.S.  submarine  forces’  strategic deterrence objective, will allow the United States and its allies  the  ability  to  deter  further  hostile  action worldwide. 5-36 Student Notes: