It's Washington's longest-running hit. Don't even try to see it on a weekend evening - the place is packed. Any other time is usually okay. To get there, be northbound on the GW Parkway. Just after the airport, take the only right turn in sight, into the parking lot. Get out, walk around, kick stones for a minute or two. Then look up the river and you'll see them coming - TWA, Delta. American, in the last moments of their approach, about to blast the bejesus out of you, seconds before they set down on runway 18 just beyond where you're standing.

Sit down, lie back on the grass and look up. The show's on.

"Some friends said to me, a friend explained, 'let's get some beer and go sit at the edge of the runway.' I'd just moved here and had no idea what they were talking about. I thought they were crazy."

He and a lot of other people. After all, what's the attraction watching the belly of the Eastern shuttle bearing down on you, shaving the air overhead so close you could spit, touching down seconds later no more than a good discuss-toss away? What is it that packs 'em in at Gravelly Point?

You'd be surprised.

"It's erotic, when you think about it."

"It's better than Star Wars."

I wave to the pilots."

"I like anything that moves. I go to train station, too."

"It's a cheap thrill."

There are some identifiable types. Take the aficionados, for example, the people with aerodynamics in their blood who can't help themselves. A feeling comes over them, and the next thing they know they're racing along the parkway, obeying the call. The ones who've got it bad go two or three times a week.

"Doesn't the noise get to you?"

"You expect it. It's like loud rock music. The ground shakes, you can feel your thorax vibrating."

More often than not these are the ones with VHF radios pressed to their temples, eavesdropping on the pilots talking to Tower Approach or Departure Control.

It's enough to astonish a passerby - grown men walking around with square boxes tight to their ears, little antennae sticking up out of their heads. Do you step on it and get the hell out of there or stick around to catch a glimpse of their ship?

But VHFers have good stories . . . makes you want to get one yourself.

"Yeah, there was a close call about a month ago, There was a little prop jet over there on runway 15 and this National jet coming in on 21.1 thought it was close myself, and then the National pilot comes on and says, "I don't like the way this looks." The tower agreed and told him to abort.

"Then you get a fly-over once in a while. A guy last week thought something was wrong with his landing gear so he flew over the tower and they checked it out with binoculars."

Many VHFers are pilots themselves, understudies. They have that same look of longing in their eyes."I just got my pilot's license a few weeks ago. I come out here to see how the big boys are doing."

Then there are those who come for love. A couple sitting close on the grass, talking softly, the remains of a picnic all around, on a wicker basket between them a half-filled glass of wine, rippling as a plane tears through the air 100 feet directly overhead.

A young man and his pregnant wife, arm in arm. He pats her stomach whenever a plane goes over. "I'm just letting him know everything's okay," he says.

A couple from Greece. "It's romantic," the woman says.

And there are people who come only when the moon is full.

In July, 28,833 planes flew into or out of National Airport, an average of 930 a day or one every 58 seconds. At the Point they are 100 feet off the ground, 400 feet from the edge of the runway, traveling at an average speed of 160 m.p.h. and will touch down approximately six seconds after they pass overhead. The average commercial carrier grazing past weighs 100,000 lbs, and creates 36,000 lbs. of thrust, more than enough to knock over unwary sailboats in the nearby channel. A sign warns them about jet blast.

The Park Service manages the point. They meant it for boat enthusiasts, but they don't object if you steal a look at a DC-10 now and then. "Our parks have a way of evolving," a spokeswoman says. They remind users, however, that alcohol is forbidden on the grounds, as are all other illegal stimulants. Only planes can be high at Gravelly.

Th peak hours are probably between 4 and 7. Night viewing has it over day viewing: "It's scarier at night," Landings over take-offs: "The planes are closer, the gear is down, the flaps are lower. There's more to see." Normally they come from the west and follow the river in. You see them lined up, spread out against the sky in an arc. The noise builds, the lights cut into the dark, the black underside screams past, and it all ends in a fading whistle.

There's one other group represented at the point, in unknown numbers. These are the unabashed thrill-seekers, people who enjoy stretching their luck. Mild-mannered types, perhaps, numb from sitting behind mid-level desks all day, desperate for a quick fix of electricity to jolt their personalities back on. Ask them why they're there and they burst into poetry.

"It's a real adrenalin pumper. They're stacked up like trays, and then one will spin off and just drop down on you. The grass curls up, the ground shakes, the air [becomes] ionized; you hear this blood-curdling shriek. It's like it's going right through you. Then you feel the aftershock of noise and air and heat."

"How often do you come out here?"

"Whenever I feel the need."

"It's like you've gone to the border line," one woman says, "and survived. If anything went wrong, you'd never get away in time. Once when we were watching it seemed like each landing got progressively worse. I swear, one plane's wings were fluttering."

You can do other things at Gravelly Point. Play soccer, fish, ride bikes, just about anything you like. Except for one thing and the sign's pretty emphatic about that: NO KITE FLYING.