Carl Franks was writing a final paper titled "Plants in the Southeast" when his former coach at Duke, Steve Spurrier, rang him up and asked him to come on down to play for his Bandits in Tampa.

Franks, an obliging sort, arrived for practice on Thursday and ran 18 yards for Tampa Bay's winning touchdown yesterday as the Bandits provided the Washington Federals with their seventh USFL loss in eight games, 30-23, before a damp crowd of 9,070 at RFK Stadium.

"Coach Spurrier said I could go back down to Duke Tuesday and hand in my papers," said Franks. The Duke senior moved from fullback to tight end two years ago, but yesterday he found himself parked behind quarterback Jimmy Jordan with 2 1/2 minutes to play in a tie game.

"Jimmy gave it to me to go off left tackle," Franks said. "I bumped in there, but it was closed so I turned it back out the other way." Franks changed his direction and the course of a tight game.

"It's a lucky thing I went to the old football firehouse in the East," said Spurrier, whose Bandits now lead the Central Division with a 6-2 record. At Duke, Spurrier was offensive coordinator. He drafted Franks on the 23rd round, but the senior elected to finish his degree.

"I think that was about the best run I've ever seen," said Jordan, who played in place of injured starter John Reaves and completed 30 of 45 passes for 345 yards and three touchdown throws to Eric Truvillion, a rookie from Florida A&M. Reaves broke his wrist last week and will miss at least another six weeks.

Truvillion, who caught touchdown passes of 28, 15 and six yards, all in the first half, said, "We had good pass protection all day and we were able to slip the zone a little bit."

Federals Coach Ray Jauch said, "They were getting behind our linebackers, and our corners got beat on some deep balls."

The Federals found themselves behind, 20-6, at the half, having matched Truvillion's three touchdown catches with only one score of their own--Eric Robinson's 94-yard kickoff return with 6:41 left to play in the first quarter. Robinson's run, which followed Truvillion's first score, is the league's longest.

Starting quarterback Joe Gilliam did not throw as sharply as he had last week against New Jersey.

Doug Beaudoin, who played with the Patriots, Dolphins and Chargers in the NFL, intercepted Gilliam three times in the first half. Beaudoin's interception in the end zone with nine seconds left, after Gilliam had completed three quick passes to get within scoring range, was particularly significant.

Federals wide receiver Mike Harris returned the second-half kickoff 71 yards to the Bandits 19. Mike Hohensee replaced Gilliam, who completed eight of 15 passes for 107 yards.

On first down, Craig James took a handoff, cut off right tackle and went in to make the score 20-13. James, who finished with 60 yards in 15 carries, said of the muddy traction, "I felt like I was drowning out there."

Jordan continued to throw well in the following drive, but Mike Guess intercepted him after the Bandits had converted five first downs on the drive. Linebacker Alonzo Johnson, however, deflected two of Hohensee's passes and rushed him on another to help get the ball back. But on first down at their 30, Jeff McIntyre knocked the ball out of running back Sam Platt's grip and safety Doug Greene recovered on the Bandits' 33.

On second down, Hohensee tripped over his own man as he went back to pass, but he pulled himself up before he was touched and threw a 16-yard completion to Harris. Two plays later he hit Mike Holmes on a 10-yard scoring pass in the right corner of the end zone with 7:04 left to tie the score at 20.

After a punt, Hohensee led the Federals to the Bandits' 13-yard line with passes to Holmes and Harris. But Washington lost the opportunity when James slipped in the mud before he could reach Hohensee's handoff.

Dale Castro, who joined the team Saturday, converted a 23-yard field goal with 12:33 left and the Federals led, 23-20. Next drive, Zenon Andrusyshyn tied the score with 9:52 remaining on a 31-yard kick.

The Federals began what they hoped would be the winning drive on their 22 with 6:01 left. After a two-yard run by Taylor, Hohensee underthrew Mike Harris. Cornerback Leon Williams intercepted on the 43.

Several runs and a 15-yard completion from Jordan to former Redskins wide receiver Danny Buggs brought the ball to the Federals' 18.

It was from there that Franks, the botanist, uprooted Washington's hopes with his scoring run.

After the game, Federals owner Berl Bernhard was feeling the effects of his seventh loss and 12,545 no-shows. This was the third time this season that the Federals played in the rain, and the crowd was the smallest yet.

"Hey, Ray," Bernhard said to Jauch. "When are we going to get some sun?"

Jauch, with nearly a half season of miscues behind him, thought briefly of training camp.

"Maybe we'll go back to Jacksonville and start all over," said the coach to the owner.