Perry Is Sworn In as Defense Secretary : Military: Aspin’s deputy takes oath same day Senate votes, 97 to 0, to back nomination. Confirmation caps almost two-month search for a replacement.

William J. Perry was sworn in Thursday as President Clinton’s new secretary of defense, ending a 7 1/2-weeklong effort by the Administration to replace departing Secretary Les Aspin.

The 66-year-old former Stanford University engineering professor took the oath of office in a private ceremony at the Pentagon after the Senate voted, 97 to 0, to confirm his nomination. Earlier, the Senate Armed Services Committee had endorsed the appointment unanimously.

The vote Thursday followed a 3 1/2-hour hearing before the Armed Services panel on Wednesday during which Perry, who has served as Aspin’s deputy for 11 months, won unabashed plaudits from senators for his stand on national security issues.

The new defense chief faces a spate of challenges and problems in guiding the military Establishment through its post-Cold War cutbacks. One of his first assignments will be to present the Administration’s new defense budget to Congress next week.

The confirmation was rushed through at the request of the Administration, in part, so Perry could attend an international conference of defense ministers in Munich this weekend.

Perry is expected to leave late today and return to Washington Sunday evening.

A high-technology expert who has become known as the godfather of the radar-evading Stealth bomber, Perry has spent the bulk of his career in the defense industry, as a consultant on super-secret weapons projects.

But he is expected to move easily into broader defense issues, from ensuring military preparedness to developing a national strategy for U.S. intervention in situations such as those in Somalia and Bosnia.

Clinton initially nominated retired Navy Adm. Bobby Ray Inman, a Texas businessman, to replace Aspin, who resigned under White House pressure.

The President was embarrassed politically when the admiral backed out of the nomination, saying that he did not want to face criticism from Congress and the media.

After a week of consultations, the White House eventually asked Perry to take the job, and announced his nomination formally on Jan. 24. Perry served in the Pentagon during the late 1970s as undersecretary of defense for research and engineering.

He is expected to go along with policies hammered out by Aspin on such issues as the size of the armed forces, homosexuals in the military and women in combat and to leave most key staff positions virtually unchanged.

But colleagues said that they expect him to be more decisive and articulate than his predecessor and better at managing the Pentagon.

They also predicted that he will abandon Aspin’s efforts to thrust the Defense Department into the heart of the Administration’s foreign policy-making apparatus.

Aspin, who had agreed to remain in the post until his successor was sworn in, had come under criticism from opponents of the Administration’s policies, and took the blame for a failed U.S. raid in Somalia on Oct. 3 that resulted in the deaths of 18 servicemen.

Aspin earlier had refused a request to send more tanks to support U.S. troops in the troubled African nation.

But the 55-year-old former Wisconsin congressman has been praised in recent days for having shepherded the Pentagon through such controversies as the gays-in-the-military issue and for initiating the “bottom-up review,” a sweeping overhaul of basic defense policy.