By Dale Eisman

WASHINGTON -- The Navy's top leadership has decided to pursue radical changes in the size and shape of its forces, likely resulting in the service shrinking by "thousands of sailors" and scaling back plans to add a substantial number of ships in the next few years, a senior Navy official said Friday.

Speaking on condition of anonymity, the high-ranking official suggested that the success of a "sea swap" experiment, in which crew members have been rotated to keep destroyers on station overseas for up to two years, has led Navy leaders to conclude they can provide the combat power the nation needs with fewer ships than the 375 they had projected.

The Navy now has 295 ships.

In a 90-minute session with reporters, the official sought to "connect the dots" on a series of hardware and manpower initiatives sketched out in recent speeches by Adm. Vern Clark, the chief of naval operations.

The ambitious agenda, much of which would need the blessing of Congress, apparently was a major focus of a meeting of more than 200 admirals at the U.S. Naval Academy earlier this month. The official said it is aimed at making the Navy, and the Marine and Army forces it supports ashore, more agile in pursuing terrorists as well as fighting more traditional land and air forces.

The plan dovetails with Defense Secretary Donald Rumsfeld's calls for military "transformation" and the development of forces that can respond more quickly to crises. It puts a premium on the deployment of relatively small groups of Marines, watched over by a network of unmanned planes and protected by Navy fighters and new naval guns that will be able to hit precise targets from 100 or more miles offshore.

The plan also calls for development of "sea bases," built around a fleet of 12 aircraft-carrier sized cargo ships with flat decks that could launch large cargo planes to deliver equipment to forces ashore.

"Sea basing" has been one of Clark's major goals for more than two years. The official said Navy leaders have concluded that the problems the United States encountered last year in securing permission to launch attacks on Iraq from Turkey are likely to be repeated in other countries as American forces pursue terrorist groups.

By stationing forces at sea, the United States avoids having to seek permission from other governments to strike at those terrorists, Clark has said.

The official suggested the first of the new cargo ships could show up in the Navy's 2006 budget plan. Along with them, the Navy and Marines are pursuing a new amphibious assault ship, with enough deck space to accommodate perhaps 20 of the F-35 Joint Strike Fighters the two services are developing in conjunction with the U.S. Air Force.

Those planes, which are to have a range of about 800 miles, also are vital to what the official said is the "persistent precision" needed to protect smaller groups of Marines ashore.

The official said that while no new target for the size of the fleet has been set, the Navy also remains committed to several major new shipbuilding programs, including a next-generation aircraft carrier, a high-tech destroyer and a high-speed littoral combat ship that could ferry troops and equipment to potential combat zones.

The service lacks the money to pay for all those programs, the official acknowledged. To help close the gap, he said, officials are considering the elimination of three or four of the 12 "Expeditionary Strike Groups" now used to keep Marine forces forward deployed .

By periodically flying in replacement sailors and Marines rather than ferrying the ships to and from Norfolk or San Diego, the service can keep as many Marines forward with eight strike groups as it now has with 12, the official suggested. The 12 strike groups are equally split between the East and West coasts.

The Navy also is studying additional forward basing, including the movement of an aircraft carrier to Guam, where it would be closer to potential trouble spots in the western Pacific and the Arabian Gulf. Officials have refused to speculate on whether that carrier would come from the Atlantic or Pacific fleet.

Five of the Navy's six Atlantic carriers are based in Norfolk.

In addition to trimming several of the strike groups, the Navy is looking to save money by continuing to cut manpower levels, the official said. With salaries, pensions and health care costs dramatically rising, "this department cannot keep doing things they way we've been doing them in the manpower business," he asserted.

The DDX destroyer now under development is to sail with just 125 sailors, one third as many as today's destroyers, and the CVN-21 aircraft carrier is to have 900 fewer sailors than today's flattops. For every 10,000 sailors trimmed from the force, the Navy can save $ 1.2 billion annually for other initiatives, the official said.

"The manpower calculus is changing right before our eyes," the official added. The service is pointing toward an enlisted force dominated by college-trained professionals, some of whom will enter the Navy at ranks that sailors normally take years to achieve, he said.