This was the scene yesterday outside the Soviet Embassy after a Korean commercial jetliner was reported to have been shot down by a Russian plane, apparently killing 269 people:

Police had virtually cordoned off one side of 16th Street, from the Aeroflot office on the L Street corner to the University Club near M Street. The night before, police had dealt with demonstrators who had filled the streets in outrage.

But yesterday, though the police presence remained, crowds for most of the day consisted of curious passers-by who gathered across the street to observe. Yellow plastic tape bearing the words "Police Line, Do Not Cross" flapped in the breeze. And police officers, nearly a dozen of them, took up their positions.

Paul Friedlander, a 28-year-old District of Columbia police officer in wire-rimmed shades, parked his motorcycle at the curb and stood on the sidewalk.

Friedlander rides a Harley-Davidson. He can climb down ropes suspended from a hovering helicopter, and on his own time the Wheaton resident is in charge of underwater rescue for the Montgomery County Fire Department.

Friedlander spent most of his morning and afternoon police duty on the sidewalk on 16th Street outside the embassy engaged in conversation:

"Sir, you can't cross there; you'll have to go down to the corner."

Pedestrian (surprised, pointing down the street:) "What about that man down there?"

Friedlander: "Sir, you'll have to cross at the crosswalk."

Why is Friedlander doing this? Because he is a member of the Special Operations Division's Special Events team, and the demonstrating outside the Soviet Embassy is a Special Event. So is waiting for demonstrations, which is what Friedlander and three other D.C. police officers did throughout the afternoon.

"Basically, we're keeping people away so nothing does happen," said one officer. "It's preventive maintenance. Better safe than sorry."

He added, "Don't call it SWAT. It's Special Operations. We do all the things that no one else wants to do."

These are the police officers who handle barricade situations, parades, demonstrations, football games, crowds of any kind, and escort the president, vice president and other dignitaries.

They've got helicopters, boats, motorcycles, scooters, tear gas squads and bomb squads. Yesterday, they came equipped with holstered guns, tear gas, tear gas masks and walkie-talkies.

"We're the minute men," said motorcycle Police Officer Arthur Hill, 47. "Ready to go at a minute's notice."

"Oh, oh," murmured one of his colleagues, glancing at the street. "I've got to check this jaywalker out." He approached the offender, requested identification and wrote out a $5 jaywalking ticket.

"This is what 95 percent of our job is," said Friedlander. "Waiting."

They do that good-naturedly, accepting that not every crisis situation is a crisis in action. What do they do to pass the time?

"Make jokes," deadpanned 27-year-old officer Steve Gately. "Talk to all the good-looking ladies--don't put that in."

Their scooters and motorcycles are parked against the curb at the edge of the University Club, which is next door (on the M Street side) to the embassy. At the opposite end of the sidewalk, at 16th and L streets, there are more police officers performing similar duties. In between, in front of the embassy itself, are uniformed Secret Service men and District police officers. The guarded sidewalk is empty, except for occasional visitors to the embassy and freqent visitors to the University Club.

At lunchtime, there had been a steady traffic of gray- and navy-suited business men and women to the University Club. At the police line, they politely told the officers they were on their way to the club, and the officers allowed them to pass.

Most pedestrians looked up in surprise when their progress down the sidewalk was impeded by police officers and police lines, but usually they wordlessly turned back, retraced their steps to the corner and crossed the street.

"Girls, you can't cross here," said one officer to two elderly women who looked stunned. "We're just securing the area." He chatted with them briefly.

"It's boring," said Gately calmly, sitting on his scooter, eating a sandwich and drinking a Pepsi. "I'd rather be doing something else . . . Having your patience tried and tested--that's the hardest thing. Letting people get to you just asking the same questions: 'How do I get by? Why can't I go this way? You shouldn't be doing this--you should be doing something else.' He smiled. "I just try to help them out as best I can."

Gately hopes one day to ride a Harley as a motorcycle policeman. Gately's father was a motorcycle policeman who was killed in an off-duty cycle sporting event nine years ago. Two of his six brothers race motorcycles, and one is a motorcycle mechanic. Steve Gately loves motorcycles, and Friedlander and Hill--each sporting a gold pin of winged wheels on his uniform shirt--love being motorcycle officers. Sometimes, during the on-duty waiting, there is time to wax their motorcycles.

"It's a lot better than a cruiser," said Hill. "You're out with the people, not taking all the calls the cruisers do."

Hill, a 20-year veteran of the police force who worked with Gately's father, is good at this waiting game, puffing quietly on his pipe. Certainly, he's seen more excitement. In 20 years he has pulled his gun from its holster four times--but has never used it. He worked the 1963 March on Washington and also worked the 20th anniversary March a week ago. He was at the Washington Hilton when President Reagan was shot. He escorted the buses of hostages returning from Iran, from Andrews Air Force Base ("In some places you couldn't see the streets because there were so many people") and he covered the rainy-day parade for the Super Bowl champion Redskins. ("A mess," said Friedlander. "Sloppy, wet, cold, miserable," said Hill.)

Hill was on duty near the Soviet Embassy the night before President Kennedy's funeral, because the police feared violence. (There was none.) And when Martin Luther King was killed, he didn't think there would be any violence. "They called me at 3 in the morning," said Hill, "and said, 'Come in. They're burning down the city.' I went home 12 hours later."

He'd love to fly a police helicopter, but that dream is as good as dried up. "After you reach 27, they don't want to train you," he said.

Yesterday afternoon, neither he nor his colleagues had any idea about when surveillance of the embassy would end. Friedlander would be back at work this morning. But Hill has the weekend off. He has to work Monday.

"The Redskins game," he said.