Thirteen minutes after 9 o'clock, long before the cursed Cowboys did it again, there moved through the still and steamy night at RFK Stadium a sound last heard in January when the Redskins took the world by the scruff of the neck.

"WOOOOoooaaaa" (imagine a diesel horn) came the sound from the upper deck as, one more time, John Riggins moved with 18-wheeler efficiency past those dagnabbed Cowboys who ventured, one more time, into these parts and swaggered into the night with an unforgettable 31-30 victory that put the lie to all those banners drawn up by the Redskins' faithful.

"Cowboys Eat Quiche" . . . "Cowboys Make Good Hog Food." Such were the bedsheet opinions among the 55,045 customers who came to RFK to see their heroes one more time, to see them against the princes of darkness up from Texas, to see the Redskins play for real for the first time since winning Super Bowl XVII last January.

By midnight, though, the only happy folks at RFK were the hundred or so Cowboys fans who, if truth be told, had to be stunned by the unexpected rally from a 23-3 halftime deficit.

Quarterback Danny White, who couldn't remember anything last January after being knocked out by the Redskins, gave Washington one to forget this time. He threw a 75-yard touchdown pass. He threw a 51-yarder. And with barely two minutes to play, White ran one yard for the go-ahead touchdown. A silence ensued at RFK.

When last the Cowboys crossed our borders, the stakes were so high--a trip to the Super Bowl--that the customers came in a state of anxiety so acute it raised their voices a note. One false step against the Cowboys, they knew, and it was a long fall from the high wire into the slough of despair.

It was more a carnival of nostalgia last night. The wire was only a couple feet off the ground. There was not much risk in a single game, one of 16, one in which defeat can be redeemed. The 55,045 customers, in Hog T-shirts and Riggins' 44 jersey, celebrated yet. They came with the sure step born of the success last January that first caused a diesel horn to sound from on high.

Come January, Riggins' little run early last night will mean nothing. It doesn't matter. Last night, coming on fourth and one barely two minutes into the game, Riggins' two yards turned RFK into a zillion-decibel music box with 55,045 pieces at full cry in cacophony sweet to the ears of Redskins loyalists.

Riggins' little run was a piece of brutal beauty in two or three steps for the gambling yardage to keep alive the Redskins' first possession. That led to a field goal. Before you knew it, the Redskins had a 23-3 halftime lead and, at RFK anyhow, all was right with the world.

It was, one more time, the stuff of dreams. There came the song, "Hail to the Redskins." It was only halftime of one of 16 games. Five days before, the Soviets shot a plane out of the sky. A congressman was killed and his widow declared him the first victim of World War III. There is a time to fret about that, but not at 9:13 last night, when Riggins' little run moved the Redskins two yards deeper into Dallas territory, for then it was time to dream one more time.

"Ain't it unbelievable that the Cowboys would come back here?" said Joseph H. Lamb of Annandale, who carried a tiny doll in a Cowboy jersey. The jersey was No. 11, Danny White's, and the doll's head was facing backwards. "This is White when Dexter gets done tonight," Lamb said.

In fact, a late-hit penalty imposed when Redskins linebacker Mel Kaufmann hurled his body at White helped the Cowboys to the go-ahead touchdown.

"I was going to buy one of those programs," said Ewell Jordan, a West Virginian who comes to every Redskins home game. "But not if they're going to put his picture on it." The program cover was a portrait of Tom Landry, the Dallas coach.

Seven months ago, the Redskins beat Dallas here, 31-17, to win the NFC championship and move on to the Super Bowl for a 27-17 victory over Miami. That delivered an NFL championship to the Nation's Capital for the first time since the December after Pearl Harbor.

Good.

But now, as Coach Joe Gibbs has said, the Redskins need to get on with it. Gibbs doesn't wear his Super Bowl ring. Not that he wants to forget the moment. Only that he wants to remember what it was like to not be the Super Bowl champion. And there for the 55,045 dreamers at RFK last night was the beauty of Joe Gibbs' game.

That was a moment to cherish, winning it all once, and now there is, for the Redskins, a chance for another moment. The game is self-renewing. Once is not enough. The players' union bosses misled their members in selling the idea NFL owners have no desire to win and so will not pay big money for free agents. Jack Kent Cooke would buy a U.S. Air Force RC135 if he needed it to win a Super Bowl for his Redskins.

"I came here tonight," Cooke said two hours before kickoff, "heaving so many sighs, I may throw a hernia. I'm worried, I'm tense. I am on a diet of worry. Never mind that we won the Super Bowl. I want to win consistently. Whoever said consistency is the hobgoblin of little minds surely did not having winning the Super Bowl in mind."

Cooke took a trembling sip of white wine.