Too bad for Atrue Ellett. When her 1980 Lincoln Continental zoomed over the hill crest on Pickett Road in Fairfax City, she was daydreaming about lunch with her husband and daughter, just back from college in Tennessee.

That'll be $42, please.

Too bad for Kiran Starosta, too. She insisted that she was just trying to pass a dawdling car when her 1971 red Mustang popped up over the crest a few minutes later.

"You can tell it to the judge," city police officer Kevin McBrien said politely as he handed Starosta a ticket for going 42 miles an hour in a 30-mile-an-hour zone.

Watch out, Washington area motorists. Do not daydream or hurry when you drive through Fairfax City. Statistics show that you are more likely to be handed a speeding ticket by a local police officer there than in just about any other major Washington area jurisdiction.

That's not too surprising, considering that over half the city's 51-man police force is assigned to traffic control. In the final three months of 1981, for instance, each city police officer wrote an average of almost 17 speeding tickets. That's nearly twice the ticket-writing rate of police officers in number two-ranked Montgomery County.

Why? It's all a matter of geography--and self-defense, said Fairfax City police Sgt. Donald P. Taylor.

"We have a unique problem in that, even though we're only six and a half square miles and have a population of22,000, we're the crossroads of Northern Virginia," said Taylor. "If you want to go anywhere, you just about have to go through Fairfax City."

Indeed, little Fairfax City, tucked in the middle of Fairfax County, is laced by five major highways: Rtes. 50, 29 Lee Highway , 236 Little River Turnpike , 237 Old Lee Highway , and 123 Chain Bridge Road . Even I-66 crosses its northwestern corner.

About 140,000 vehicle trips are made through Fairfax City on those five highways during a typical 24-hour period, said Don Keith, Northern Virginia administrator for the Virginia Department of Highways. That's about seven car, truck and bus passages for every man, woman and child there.

"Pick another city in Virginia with the same size population and I doubt they'll have anywhere near the same volume," Keith said. "Of course, that's why Fairfax City exists, you know, right there where Rte. 123 and Little River Turnpike cross. That's where they put the county courthouse, where they watered the horses."

From October through December last year, 864 speeding tickets were written in the city. That's well below the 7,710 written in Montgomery, but then the Maryland jurisdiction has 716 more police officers, too. While no one knows exactly how much revenue speeding tickets bring in for the city, officials say about $92,000 was earned through collections on traffic violations of all kinds last year. That's not much in a city with an annual budget of about $22 million.

"The speed traps of the fifties and sixties are gone," said Sgt. Taylor. "You know, the little southern town on Interstate 50 or something, where the local policeman earns his lunch money based on how many speeding tickets he can write. We don't have quotas. We're just interested in protecting the residents. And we've got some problem streets."

One of those is Pickett Road just before its intersection with Rte. 236 near Woodson High School in Fairfax County. That's where Officers McBrien, Harley R. Shaffer and J.W. Smith set up their radar last week in an effort to slow cars that persistently pass by at five to 15 miles an hour over the speed limit of 30 mph.

"Nothing seems to slow 'em down," said Shaffer, a 10-year veteran of the city police force. "They know we work it here, yet they just keep doing it. We've written as many as 40 tickets in one two-hour shift here."

"Look," said McBrien as he pointed the radar gun at the crest of the hill a hundred yards away and clocked car after car coming into view well over the speed limit. "We've been standing here for nine minutes and five of those cars that passed were going in excess of 10 miles per hour over the limit."

"I'd say about 99 percent of the people past here speed," Shaffer laughed.

McBrien said they try to catch the most flagrant speeders--"otherwise we'd need a lot more officers here"--so on this day anyone topping 40 mph was pulled over. Generally, they allow only three or so miles an hour grace, however.

Within a short time they had written six citations.

Smith chuckled when asked what was the funniest excuse he'd ever gotten. "D'you tell 'em about the enema?"

McBrien laughed shyly. "I stopped some lady who was going about 45 in a 25-mile-an-hour zone. She told me she'd just had an enema."

Did she still get a ticket?

"Yeah," he said. "But I wrote it out pretty quick."