They are wonderful creatures that live in the sky.

In the dawn, just north of the District, Andre' Heller and his helpers pull the great, gaudy guts of nylon from huge bags and start blowing them up with electric fans.

Then hot jets are turned on, spitting yellow flames up into the hollow interiors, and the three balloons rise on their tethers. Fifty feet above the bare ground of Rosemary Hills Park, the phantasmagoric shapes tug upward like live things.

One is a vast scarlet jellyfish with tentacles of green, purple, pink, orange, beige and violet. Another is a yellow man-in-the-moon 13 stories tall, sticking out his tongue. The third is black, Kiku the Black Knight, his crew calls him, part giant seashell, part teapot. This is his world debut.

They were to have floated high across Washington yesterday, a gift to North America from the people of Vienna, but when Heller released a trial balloon (literally) about 7 a.m. it headed due south, straight for the White House, where balloons, even goofy ones, are viewed with slit-eyed suspicion.

"We cannot go today," the artist told the clustered media people. "The wind is wrong."

So he gave the media people rides. Tom Donnelly, a flying Yorkshireman with the British team that operates Heller's sky sculptures, took a passenger aboard Kiku and turned on the jet. A flame roared up and the black bag lifted eerily off the ground.

It soared to 50 feet and stayed there while Donnelly occasionally touched it up with the jet. Beside it the other balloons were aloft, contemplating each other. Every so often a flame jet would lick upwards with a hissing roar.

Below, some park police and Chevy Chase neighbors stood around the edges of the field rather shyly, arms folded, like the small boys who used to hang around Robert Goddard's early rocket experiments. A woman in a dressing gown gaped from a high-rise balcony. Some plumbers drove their van into the parking lot, drawn there like the Magi by what they had seen in the sky.

Donnelly is an architect who got into designing hot-air craft and now just flies them. Ballooning is like that. You ask Heller why he's doing this and you feel like a fool, because the answer is clear from the first instant:

It's for nothing. It's for fun. It's to spark people's imaginations, to startle them, to turn their mouth corners up.

"The governments have donated the sky to the military," Heller says. "Artists are not welcome there. I want to take back the sky."

He wants to bring art out of the museums and give it to the millions, and his balloons aren't the half of it. With a $600,000 grant from the visionary Mayor Helmut Zilk of Vienna, he is visiting some 30 American cities this summer and fall, floating his amazements across the horizons of 150 million people.

Many of his sculptures -- so aerodynamically weird that they must be elaborately partitioned inside -- look like sea creatures. Gazing up at them, you could think the air was an ocean and you were at the bottom.

When you step inside a half-filled balloon the impression is somewhere between a cathedral and a circus tent. The things cost $65,000 each, had to be designed by computer and run about 60 feet in diameter.

"I am now thinking about more abstract designs," the sculptor says. "I may make a balloon with Keith Haring. Or have one painted by Lichtenstein or David Hockney."

Popular art? Last year the balloon troupe was seen by at least 100 million people in 20 European cities. For Heller, a German rock star of the '60s who made 14 LPs including a gold record, it is the only way to go.

Heller has put his own money into his projects, many of which bring no tangible return. There is his Luna Luna amusement park in Hamburg with constructions, murals, games and toys by the likes of Dali, Hockney, Lichtenstein, Haring, Erte', Beuys, Tinguely and so on. The whole fantasy cost $7 million, about as much, he says, as a couple of rubber crocodiles at Disneyland.

There was his Theater of Fire, a stageful of fireworks on water, set to the music of Stravinsky, Handel et al. "We sold 550,000 tickets for one evening," he says. "We had the show at the Berlin Wall, and there were 100,000 people on the East side and a million on the West. It was very emotional."

There was the variety show "Flic Flac" -- with 30 quick scenes viewed as someone falling 30 floors in a dream might see them -- and the Circus Roncalli, with Schoenberg music and special action scripts for all the acrobats and tumblers. And the 1984 production in China with "these incredible athletes, the first time Chinese artists have worked with outsiders," he says.

Publicity becomes part of the technique, of course, as with the wrappings of Christo and similar projects on the grand scale. The media are conscripted as coproducers, but somehow one doesn't mind.

Probably tomorrow morning Heller's flying sculptures, Children's Moon, Dream Lab and Kiku, will float across Baltimore's sky. Then Philadelphia, then New York (the only other city besides Washington that disapproves) and on around the country, completing the circle in Florida in November.

"So many people are controlled by machines," Heller says. "Art has to be more fascinating than video games, more fascinating than 'Dynasty.' We must give children a reason to go to the window and not sit in front of the tube."

About those tongues: One sticks out of Children's Moon, waggling crazily into the air 20 feet or so. One curls out of the monument of flowers in Berlin. What do they mean?

"This comes from my childhood," says Heller, scion of a wealthy Vienna confectioners' family. "It is rude behavior. It makes fun of yourself and everyone, a gesture of joy and freedom."

He wants to remind people of their own creativity, he says. He hates "the whole cynical industry that is consuming people's free time -- the television, the video games, the drugs of all sorts." It is the duty of art, he says, to fight back.

That's what everyone was doing out there at Rosemary Hill, lining up for rides in the flying sculptures. Maybe there is still room in the world for a man who wants to commandeer a squadron of airplanes -- for a ballet