Ray Jauch was looking for spies. In search of George Allen's agents of terror and espionage at the Federals' first workout here yesterday, he pointed to a dark tower looming above the RFK Stadium practice field.

"I thought I saw someone climb up there," said the Washington coach. The tower, though, was free of human presence. If there was a spy peering out with binoculars in one hand and a clipboard in the other, he lived only in Jauch's imagination and wit.

It would be understandable if Allen or Jauch did decide to hire an underground scout or two in preparation for their United States Football League matchup on Sunday. Needless to say, there are no regular-season game films available of either the Federals or Allen's Chicago Blitz.

"Films? Hell, we just got their roster today," said Defensive Coach Leo McKillip. "We don't know much about Chicago, except we know they have that running back, Tim Spencer. And that wide receiver. What is it, Gene?"

Gene Stauber, the defensive line coach, had that tidbit covered.

"Trumaine Johnson is the name that comes to mind," said Stauber.

The Federals coaching staff is well aware that the Blitz will feature Spencer, Johnson and Greg Landry, the former Detroit Lions and Baltimore Colts quarterback, on offense and ex-Lions/Colts linebacker Stan White on defense. But after that, it's all a little mysterious. Jauch may have to rely on serendipity more than he might prefer for his game plan.

Washington put the finishing touches on its roster shortly before practice. To cut the playing roster to 40, the Federals released former Redskins and Colts defensive end Dallas Hickman, wide receiver Rod Goosby of University of Nevada at Las Vegas, defensive back Hollis Hall of Clemson and wide receiver Chy Davidson of Rhode Island.

Hickman, who played six years with the Redskins, was trying to win a spot with the Federals at outside linebacker. With Coy Bacon, Drew Taylor and Mike Barber at defensive end, the coaches felt Hickman would have a better chance of making the team at linebacker, where the talent is not nearly as deep.

"We decided to keep only four linebackers," said McKillip. "But I know Dallas can play in this league. I wouldn't be surprised to see someone pick him up pretty soon."

The Federals announced a starting lineup that has Kim McQuilken at quarterback, James Mayberry and Craig James at running back, Dave Pacella, Myke Horton, Bruce Byrom, Chris Dolce and Joel Patten on the offensive line and Reggie Smith, Phil DuBois and Marc Brown at receiver.

On defense, Washington will start Taylor and Bacon at end, Bennie Smith and Ron Estay at tackle, Farley Bell, Ed Baxley and John Zupancic at linebacker, and Gregg Butler, Jeff Brown, Donnie Harris and Doug Greene in the backfield.

Obed Ariri will be the kicker and Steve Hoffman the punter.

The Federals took the field about 3:30 p.m. yesterday. Located behind D.C. General Hospital and RFK's Parking Lot 8, the field was used by the Redskins until they began working out at Redskin Park in Chantilly, Va., 12 years ago.

While the occasion was no Super Bowl, and there were only a couple of television cameras around to record it, there was a modest bit of ceremony surrounding the Federals' first practice at RFK.

But when the players arrived at the field they discovered the gate was covered with dead vines and branches and bolted shut.

"Get out the machetes and hack your way in," Jauch told his players.

And then he remembered his adversary, Chicago's reigning master of espionage.

"This must be George Allen's plan," said Ray Jauch, prying back the gate.

A Federals "Welcome Home" luncheon is set for the Touchdown Club (2000 L St. NW) at noon today. The event is open to the public.

The Quarterback Club of Washington will feature the Federals at a luncheon at noon Friday at the Touchdown Club.