At five minutes till 11, a White House aide came out to vacuum the red carpet.

At five minutes after 11, the shiny silver Rolls-Royce whooshed up the White House drive carrying the future king and queen of England.

The first thing one notices about Diana is that she is rod-thin and tall, and in her red pumps, considerably taller than her husband, towering over Mrs. Reagan, standing almost as tall as the president. When she hopped out of the Rolls in her fire-engine-red suit, the wisps of her hair showed high above Charles in his navy pin stripes, and she had to stoop ever so slightly to greet the first lady.

The two couples sipped tea and ate cinnamon toast in the White House family room for 30 minutes, the first social event in a three-day visit that has obsessed the nation's capital for months.

The prince and princess of Wales finally arrived in Washington yesterday, with 7,000 pounds of luggage, beneath a brilliant November sky and ready for a royal flush of dinners, art exhibits and brunches. They were escorted through the day by the press, the power brokers, and large crowds, thousands and thousands, who turned out for a look -- mainly at Diana. It is her first trip to this country, and his seventh.

They looked happy and rested despite the fact that they had just completed a 15-day visit to Australia, an 18-hour stopover in Hawaii, and a 12-hour flight to Washington aboard an Australian Air Force jet.

"I haven't slept in two days," Diana told an elderly woman at the Washington Home and Hospice, one of her stops yesterday.

"I am trying to get over the jet lag," Charles acknowledged at the American Institute of Architects, one of his stops. And during the slide show there, his eyelids appeared to get heavy.

The day began early for many others, too. Just after sunrise, Andrews Air Force Base looked like Connecticut and K at noon. A line of 4,000 people, many waving British flags, stretched from the jet to the helicopter that whisked them to the British Embassy for a jampacked day and a sparkling White House dinner that may have the most stellar guest list of this administration. White House, Round 2 ----

Blass! Dior! Galanos! Herrera! Red! Gold! Hot Pink! Emerald! It seemed that the cream of U.S. society took Diana's fashion reputation seriously last night. They put on a show unrivaled at a White House dinner, with one gown more breathtaking than the one before.

Or at least as breathtaking: Some noticed that Carolyn Deaver and Moira Forbes Mumma appeared to be wearing the same dress, which had a hot pink satin skirt with black velvet bodice.

Nancy Reagan wore the white Galanos gown she wore at the last inaugural. Diana's dress was a long evening gown by Victor Edelstein in midnight-blue velvet. The sleeveless bodice was "ruched to a low hipline, which is trimmed with a bow," according to the embassy's official description. The skirt was flared. She wore long dark-blue suede gloves and a pearl choker with a sapphire clasp.

The toasts were predictably rosy, with two slips. President Reagan first referred to Diana as "Princess David." Charles got his script right, but forgot the point. He sat down before he toasted. A moment later he jumped up and said "I've forgotten the toast" and raised his glass to the president.

President Reagan welcomed Their Royal Highnesses to the White House, and expressed delight in meeting Diana. "Our two countries are bound together by innumerable ties of ancient history and present friendship . . . we stood together through two great world conflicts. Today, we go on shoulder to shoulder in an alliance to protect freedom and democracy . . . "

"Your Royal Highness, in the eyes of my country, you and your family hold a place of high honor . . ." In the end, he toasted "her majesty, the queen."

While Reagan was talking, Charles fidgeted, playing with his menu card and his cuffs and neatly folding his napkin. When Reagan finished speaking, no one applauded. Mrs. Reagan looked surprised and seemed to cue those sitting around her. Meanwhile, Diana joined in raising her glass to the queen but never looked up, keeping her chin and eyes down as she had done throughout the day.

Prince Charles said: "You really have touched both my wife and myself deeply this evening by your extremely kinds words. We can't thank you enough for your immense hospitality and your great kindness . . ."

It was Mikhail Baryshnikov's lucky night -- he sat to the right of the princess, while Reagan sat to the left. And Beverly Sills had the honor of being Charles' dinner partner, with Nancy Reagan to his left. Singer Leontyne Price, Jacques Cousteau, Dorothy Hamill, Steve Lundquist and Lee Annenberg were also at the president's table. William F. Buckley, Peter Ueberroth, Suzanne Farrell and Peter Ustinov sat with the first lady.

Guests had begun to arrive at 7:15, and were exceptionally cooperative with the clamoring media.

Photographers started cheering "Clint! Clint!" when Clint Eastwood, sporting a new punkish hairstyle, swaggered in, sexy as ever. "Are you going to asked the princess to dance?" the reporters called out.

"I didn't know we were dancing," Eastwood said. "I'll probably do a little Fred Astaire work."

Eastwood, one of those guests requested by the palace, said he read in the newspapers that he had been invited before he received an invitation. "Then Mrs. Reagan called me and I said 'Why not?' "

Several others were also asked if they would dance with the princess, including actor Ustinov. "No problem there," he said. "Once I was asked to dance by the queen. I said 'I don't think you know what you're in for.' And we actually did retire after two steps."

John Travolta, who made his mark dancing in "Saturday Night Fever," said he would certainly ask the princess to dance if it was "permissible."

Asked if she would dance with the prince, skater Dorothy Hamill looked at Dean Paul Martin and said, "May I? If he'll let me, I'd love to."

"I'm so nervous my stomach is all butterflies," said singer Neil Diamond, a favorite of the princess. "I'd rather face an audience of 20,000."

"I was enormously flattered," said Tom Selleck. "I flew from Hawaii for the last 22 hours just to meet them and I'm going right back tomorrow."

First friend Betsy Bloomingdale, with her escort Texas oilman Edwin Cox, arrived wearing an eye-catching gold velvet Dior that seemed to glow, with gold shoes to match.

Reporters asked Bloomingdale what she thought of the idea of the prince and princess -- who will visit a J.C. Penney store Monday -- visiting Bloomingdale's. "Why not?" she shot back. "The queen went to Bloomingdale's!!" The Royal Reign

Consider the White House guest list last night as a kind of barometer for the kind of value this country places on royalty. Included were some of the best in their fields: discoverer of the oral polio vacine Jonas Salk, architect I.M. Pei, author Larry McMurtry, cosmetic queen Estee Lauder, artists Jamie Wyeth and Helen Frankenthaler.

Diamond, Eastwood and Travolta were on hand at Diana's request. Leontyne Price, who performed, and her brother, who accompanied her, were the only black guests. Maureen Reagan, with her husband Dennis Revell, was the only other member of the Reagan family there.

Buckingham Palace requested that some of the guests be in Charles and Diana's age range. At 36, Charles is 12 years older than his wife.

The relatively simple menu for the event included Maryland crab, glazed chicken and peach sorbet, with California wines. Price was to sing popular opera selections and one spiritual, "Every Time I Feel the Spirit."

Outside the White House several hundred demonstrators from a group called Irish Northern Aid loudly chanted "IRA All the Way." "He's the future and we want to let him know how we feel," said Mary Baggarly, a member of the organization.

But for the most part, Washington seemed to be left breathless by it all.

"There is no other woman in the world who could come to this White House and create this kind of hysteria," pronounced James Whitaker, affectionately called the official "royal snoop," a London gossip columnist who has made a career out of stalking Charles and Diana.

"I think it will be smashing -- for both sides," British Ambassador Sir Oliver Wright was quoted as saying. Wright gave up his silver Rolls for his house guests, and will be driving his wife's Jaguar until Tuesday.

Hostesses here have been clawing for weeks for invitations to the social whirl, but at least one Washington multimillionaire gave up his big chance. Redskins owner Jack Kent Cooke declined an invitation to Paul Mellon's exclusive lunch for the royals in Middleburg today.

"Miss Dallas? Are you serious?" Cooke was quoted as saying. Getting Around Town

For the most part, the couple traveled through town in a six-car motorcade buffered from the press and fans. But at the American Institute of Architects, Charles chatted with some reporters.

He told them that "sadly" he only had "rather a short discussion" with President Reagan earlier in the day.

Of his AIA conference he said: "A good way for me to learn what's been going on over here for the last 15 years." He said he was enjoying himself "very much." He said he only wished he had time to go to Baltimore to look at the Inner Harbor development. He was interested in the "economic activity it has generated. It gets more people than Disneyland."

Diana didn't disappoint her fashion-watchers at Andrews, showing off a tall, boxy, red hat -- somewhere between a pillbox and a toque. The suit was wool, designed by Bruce Oldfield, one of her favorite designers.

The Sunday Telegraph in Sydney reported yesterday that Diana was so "stunned" that her clothes in Australia were being criticized as dowdy, she sent to London for a red outfit. The paper reported that the outfit, presumably this suit, was rushed to her yesterday via Korean Air.

From Andrews, Charles and Diana had been flown directly to the British Embassy by helicopter to "dump their luggage," as Burns put it.

Immediately after the morning visit to the White House, they returned to meet the staff and, in keeping with royal tradition, to plant a maple tree.

Following a change of clothes, Charles headed for the American Institute of Architects, while Diana, escorted by Barbara Bush, went to the Washington Home and Hospice for the terminally ill. About 2,000 were outside there to greet her. Following that, the two met back at the British Embassy at an off-the-record reception for 100 American reporters. "Just so that you know what they look like," said Michael Shea, press secretary to the queen. The Press

More than 300 reporters and cameramen trampled, shoved and haggled for hours for one glimpse of the couple at the White House. And a throng of British press was being herded like cattle from event to event. They made the American press look as serene as an audience at the Royal Ballet.

"They speak so cultured, and act like animals," said Norma Nathan, gossip columnist for The Boston Herald, about her British competition. "One hit me in the head with his bag and another knocked my glasses off. I'm just glad my Blue Cross was paid up before I left Boston."

When Charles and Diana left Andrews at 9:07, the gates cordoning off the 350 press members were opened and reporters, cameras, notebooks and tripods came spilling through like water over floodgates, running over to the still lingering spectators, particularly crowding around anyone who touched or spoke to the couple. The Arrival and the Wish ---

The royal couple arrived on a Royal Australian Air Force Boeing 707, and when the doors of the plane opened, U.S. Chief of Protocol Selwa Roosevelt and Anne Beckwith-Smith, Diana's lady-in-waiting, walked together onto the plane and out of sight for about a minute. When they came back into view, they were followed down the stairs by Charles and then Diana.

At the red carpet, Charles and Diana lingered as they greeted the dignitaries in the receiving line, beginning with Ambassador and Lady Wright. Diana, looking relaxed, chatted and laughed with Lady Wright. Most of the women in the receiving line curtsied to Diana and Charles.

"I asked her to see her engagement ring," said Ann Waymire of Springfield later. "It's so big. It sparkled so pretty." She cried as she retold the story.

The first to greet them after that was a group of handicapped people, and Diana lingered, talking with someone in a wheelchair.

She was given a small shopping bag and then an album of songs by Jonathan Lollar, of Ocean Springs, Miss., a 16-year-old boy who has a brain tumor and was granted his wish (by the Make-a-Wish Foundation) to see the princess. The album is of him singing gospel songs.

"I told her I hoped one day to see her in London," said Lollar. "She said, 'Oh, that would be great.' She said she hoped I got to come, too, and to let her know. There's no one else in the world like her."

As for Charles, said Lollar (who stands 53 inches tall, his growth stunted by his illness), "He's cool. I'm jealous of him. He gets to live with her all the time."

This is Jonathan's biggest wish. "She's not real," said Jonathan, who has been blind for five years. "She's too gorgeous."

"Oh, no, he's never seen her," said his mother, Dorothy Lollar. "He knows what I tell him. But in his mind, he sees her as blond and beautiful and precious." The White House, Round 1

For a brief moment at the White House yesterday morning, it appeared as if the president's plaid jacket might upstage Diana's red suit.

Reagan had added a personal British touch to the White House reception for royals by wearing a very bright jacket made of his mother's family tartan.

A White House spokesman said the green, blue and red plaid was that of the Wilson family, the president's Scottish ancestors. The president's middle name is Wilson. "He's worn it at Christmas parties before," said Elaine Crispen, the first lady's press secretary.

The first lady, who usually favors red herself, wore a Geoffrey Beene beige wool dress, with wide suede belt and gold choker.

Charles wore a dark-blue pin striped suit, with double vents. On his lapel was a small red poppy, commemorating Remembrance Day, the British marking of the end of World War I.

The car flew the prince of Wales' standard, which showed a lyre and some stylized British lions. There was some quiet banter among the the two couples, then Reagan, gesturing, started steering his wife by the arm in the direction of the house.

Crispen said Mrs. Reagan told her that earlier in the morning Charles and Diana sent her a bouquet of pink roses and begonias, baby's breath, queen lace and larkspur.

With the bouquet was a 12-by-18-inch black leather photo album inscribed, on the cover, with, "Ronald and Nancy." It did not contain any photos.

The president gave Charles an old deed, which is a link in the chain of title to Sandringham, the royal estate in the county Norfolk.

The first lady gave the princess a sterling "Dates to Remember" calendar with special dates noted. Diana at the Hospice -

Why would two little girls spend a beautiful Saturday afternoon waiting on a sidewalk outside the Washington Home and Hospice?

"Because she's a Diana freak," said Katie Tiedeken, 10, pointing her finger directly at her sister.

"She's just really neat," said Serena Tiedeken, 15, explaining why.

The Tiedekens came from Pennsylvania to catch a glimpse of Princess Diana. The crowd of about 2,000 others gathered there included lots of children who rolled around on the lawn, about a dozen postal workers who sat up on the high brick wall between the hospice and the post office next door, a pack of press roped off near the driveway, and groups of friends with cameras and binoculars. They all came to see Her.

Diana's arrival was heralded by several wolf whistles, courtesy of the home's 11-year-old cockatoo named Capricorn. If Diana noticed she did not acknowledge it and immediately set about shaking hands with the residents who had been waiting for more than a half hour.

She stopped to talk to each wheelchair-bound resident, holding on to the bouquet of orchids, carnations and mums presented to her by Irene Keyworth, 93.

For almost a half hour, Diana chatted quietly, patted hands, leaned close to hear soft voices, and, in turn, to speak into ears that were hard of hearing. Behind her a couple of paces was Barbara Bush, also wearing a red dress. Taking it all in at the far end of the line, which snaked its way around the hall, was Mary Bryan, who will be 100 in December. "By the time she gets around here I'll be dead," Bryan told her companions.

"You are very pretty," said Dorothy Miles, 85, the keeper of the home's birds, including the cockatoo.

And when Florida Graves, 99, said, "Oh, your royal highness, thank you so much for coming to visit us," Diana extended her hand with an apology. "It's a very warm hand," she said. "I'm sorry -- it's these lights."

She told another patient, Pauline Boone, 87, "I'm sorry you had to wait so long."

On a small raised platform Diana joined Mrs. William R. Pendergast, president of the home's board; on the wall behind them was a small curtain, which, when pulled by Diana, revealed a plaque commemorating her visit.

Pendergast told Diana that Corinne Phillips, 76, president of the Resident's Council, had a small gift to present. Instead of waiting for Phillips to wheel herself across the floor, Diana strode off to meet her. Said Phillips, "The ornaments are given with appreciation for your interest and concern for the elderly. We thank you." Then she backed off taking with her the box of ceramic ornaments especially made for the occasion by the residents.

Diana looked around at Pendergast, turned beet red and decided to go after Phillips to get the box. She did, blushing deeply by this time, then turned and walked with the rest of her entourage out the door at 3:50 p.m. Charles and the Architects

When Charles stopped by the American Institute of Architects, he was both a student and a complimentary bon vivant. When he first arrived, he pointed to an office assistant, Leslie Harrell, and said, "I like your blue dress."

In the discussions and tour, where he stayed almost seven minutes more than scheduled, Charles asked Baltimore and Savannah, Ga., community housing activists about rehabilitation and preservation of their neighborhoods.

"He said he was interested in public and private partnerships to rehabilitate areas and he asked the participants how do you go about getting community leadership and elected councils to listen to people," said Mary Means, president of the AIA Foundation.

Before he left adjoining Octagon House museum, Charles looked at the Treaty of Ghent, the one that ended the last war between Britain and America, the War of 1812. "Is that kept here?" he asked. Means answered that it was usually kept at the National Archives, adding, "They don't trust architects." Charles laughed and agreed. "Can't trust them."

While Charles was inside, the crowds outside in the crisp autumn air had swelled from 300 Royal Stalkers to almost 1,000 curious fans. Christina Kirk, 19, an English major at Towson State University and a self-proclaimed champion of the royals, was trying to hoist up a sign that said "Happy (Almost) Birthday Charles." He will be 37 Nov. 14.

"They are my hobby. Some people like athletes, some people like rock stars. I like royalty," said Kirk, who was wearing a copy of the sheep sweater that Princess Diana had popularized. When he appeared and waved to the cheering crowd, Kirk and two friends lifted the sign. "I really don't think he saw it," Kirk acknowledged, "but we are going to try again at the National Cathedral and at the National Gallery."

Eloise Daniels, a retired housekeeper, came to tell the prince about her apartment in Savannah's Landmark Inc.-rehabilitated Victorian section, and made a pine needle basket for the prince that he took with him.

His departure was delayed because he stayed to see the show of British architectural drawings.

On his way out, he gave a hearty call of "Cheers" to the staff and the press. And off he went. Guests at last night's White House dinner for TRH Charles and Diana:

British Ambassador Sir Oliver and Lady Marjory Wright

Sir John Riddell, private secretary

Michael Shea, press secretary

David Roycroft, assistant private secretary

Anne Beckwith-Smith, lady-in-waiting

Lt. Cmdr. Peter Eberle, equerry

Princess Yasmin Aga Khan, daughter of the Aga Khan and Rita Hayworth

Leonore Annenberg, former chief of protocol

Brooke Astor, New York

Dr. Robert B. Ballard, Woods Hole Oceanographic Institution, and Marjorie Ballard

Mikhail Baryshnikov, American Ballet Theatre

Betsy Bloomingdale, Los Angeles

Daniel J. Boorstin, librarian of Congress, and Ruth Boorstin

J. Carter Brown, director, National Gallery of Art, and Pamela Brown

William F. Buckley Jr., editor in chief, National Review, and Patricia Buckley

Capt. Jacques-Yves Cousteau, marine explorer and film producer

Edwin L. Cox, Dallas

Michael K. Deaver, public relations, and Carolyn Deaver

Philippe de Montebello, director, Metropolitan Museum of Art, and Edith de Montebello

Neil Diamond, singer and composer, and Marcia Diamond

Clint Eastwood, actor

William Stamps Farish and Sarah Farish, Versailles, Ky.

Suzanne Farrell, ballerina, New York City Ballet, and Paul Mejia, choreographer

Malcolm S. Forbes, president, Forbes Inc., and daughter Moira Forbes Mumma

Helen Frankenthaler, artist

Ted Graber, interior designer

Rupert Hambro, chairman, Hambro's Bank, London, and Robin Hambro

Dorothy Hamill, figure skater and Olympic gold medalist, and Dean Paul Martin

Drue Heinz, Pittsburgh

David Hockney, artist

Estee Lauder, New York

Andrew L. Lewis Jr., chairman, Warner Amex Cable Communications Inc., and Marilyn Lewis

Steve Lundquist, swimmer and Olympic gold medalist

Larry McMurtry, author

James G. Niven, son of late actor David Niven, and Fernanda Niven

Norman Parkinson, photographer, and Wanda Parkinson

I.M. Pei, architect, and Eileen Pei

Charles Price II, U.S. ambassador to the Court of St. James's, and Carol Price

Leontyne Price, opera singer, who performed, and Brig. Gen. George B. Price, her brother

Maureen Reagan and Dennis Revell

Dr. Jonas Salk, physician and scientist, and Franc,oise Salk, artist

Tom Selleck, actor, and Jillie Mack

Rear Adm. Alan B. Shepard, former astronaut, and Louise Shepard

Beverly Sills, New York City Opera, and Peter B. Greenough

John Travolta, actor

Peter Ueberroth, commissioner of baseball, and Virginia Ueberroth

Peter Ustinov, actor, and He'le ne Ustinov

Gloria Vanderbilt, New York

Charles Z. Wick, U.S. Information Agency director, and Mary Jane Wick

James B. Wyeth, artist, and Phyllis Wyeth

Jerome Zipkin, New York