The Washington Federals hired Ted Vactor, football coach and assistant athletic director for men's sports at the University of the District of Columbia, as special teams coach yesterday, completing a six-man coaching staff.

The Federals also announced the signing of offensive tackle Dave Pacella and defensive tackle Mike Corvino, cocaptains last season at the University of Maryland. As a senior, Pacella won the Jacobs Trophy as the outstanding offensive lineman in the Atlantic Coast Conference.

The team will leave Sunday for training camp in Jacksonville, Fla., as the U.S. Football League continues preparations for its first season.

The hiring of Vactor for the Federals' staff apparently means that Floyd Keith, who resigned Monday as coach at Howard University, will become a defensive aide at Indiana University under Sam Wyche, the Hoosiers' new coach.

Floyd was a finalist for the Federals' job. Today is his last day at Howard, where he coached for four seasons.

Leo Miles, Howard's athletic director, said that Joe Taylor, the defensive coordinator, will handle Keith's administrative duties until a new coach is hired. Keith has recommended Taylor as his successor. Miles said the school is accepting resumes, but has not begun a selection process.

At UDC, Athletic Director Charles Moore was unavailable for comment. But Winthrop McGriff, his special assistant, said there had been "no consideration whatsoever" on a successor to Vactor, who went to UDC after playing seven seasons for the Redskins, with which he was a standout on special teams and played defensive back.

Vactor, 38, who was in his seventh year at UDC, had been head coach there for five years.

"It was a tough decision," he said. "I left a lot of good young kids there and I'm going to miss those young guys you have to deal with every day... (But this is) the ultimate. If you want to be a coach, you want to try your hand at professional coaching. It's a chance to see if you can cut it."

Pacella and Corvino said they decided to sign with the Federals after evaluating their options while waiting for the NFL draft. Despite his ACC honors, Pacella said he has been told that, because he is only 6 feet 2 and not exceptionally quick, he likely would be selected in the fourth to eighth round of the NFL draft.