Early this month more than a hundred boats completed the 40th annual Annapolis-to-Hampton sailboat race in conditions so ideal some wondered if they hadn't died and gone to sailor's heaven.

Flying Cloud, a homemade 45-foot sloop, crossed the starting line first in her class at exactlynoon. She passed the finish in Hampton, Virginia, in the dark before dawn, with the bizarre lights of freighters and coal carriers glittering close by, at 4:29 the following morning.

That's 120 miles down the Chesapeake Bay in 16 1/2 hours, an average of 7 1/4 miles per hour. For a sailboat, it qualifies as flying.

"I don't know what to do," mused one Flying Cloud crewman. "I have a whole weekend I wasn't counting on."

It was the fastest time in more than 20 Annapolis-Hamptons for skipper Ray Brown. What astounded him, he said, is that it was so comfortable. "We hardly got a drop of water on deck."

The wind hung steady at 8 to 10 knots from the west, which made for a smooth beam reach almost all the way.

The ideal of every veteran Hampton racer is to pass Smith Point Light at the mouth of the Potomac before nightfall. On Flying Cloud the arc of the white light from the old marker swung into view just as the sun began its orange decline.

The spinnaker was full and the knotmeter was playing with 8. There were six miles to go to the mark and Flying Cloud ate them up like a hungry porpoise. The lighthouse, a gaudy mustard and pink, was fading astern as the sky went dark.

"Made it," smiled Bill Peach, the nightwatch captain.

Flying Cloud was first in her class and second in port, trailing only the 60-foot all-out racer Cayenne. No one else was close.

That would be a shocking success for just about any other homemade boat in the world. It was no surprise to Brown, 53, a basement inventor who designed this yacht from a mental picture of what a racer should be, then built it with four years of muscle and sweat. He couldn't find anybody else willing to do it the way he wanted.

"It really is something," said Gregg Lawson, crewmember and former North American 505 dinghy sailing champion. "If he had it to do over again, I don't think there's a thing on Flying Cloud that Ray would change. He just got it right."

Brown was a successful racing skipper in the 1960s, running a 38-foot factory-made Pearson called Fleetwind. He won overall honors twice in the prestigious Chesapeake fall series; was first in class three times in the Annapolis-Newport race and second twice in the Bermuda race.

But Brown, who owns a small plant that manufactures bottle openers and who has an engineering degree from M.I.T., had a special need only a special design could accommodate. He lives on a shallow creek in Hampton and likes to keep his boat there. He came with an unprecedented plan for a racer with a rectractable keel and designed Flying Cloud around that concept. It was one of a kind.

When he couldn't find anyone to build it, he expanded his brother's small boat-building shop, bought a couple tons of fiberglass and went to work.

"I'd go into the office for a few minutes every morning and then go into the boatyard and put in 10 hours' work," he said. Ten thousand working hours later, Brown had the hull and deck finished and the rigging in place.

The next year -- 1977 -- he began racing her. It would have been great if time had stood still, but by then Flying Cloud was a 1972 design facing the hottest boats that the best design minds in the world had been refining for five extra years. Though she was fast, her handicap rating against boats built to meet the handicap rule was awful.

"By 1977, the boats I had designed her to be competitive with were largely obsolete," said Brown. "I'd take my wife up to Annapolis for the fall series and we'd finish next-to-last. She'd say to me, 'Why are we doing this? We used to win races.'"

Lately Flying Cloud has profited from a new rating system. Under the so-called MHS system she can race and win again, as she did in the Hampton competition.

But the disappointment of her initial competitive failures evidently got Brown looking in other directions. At age 51, he discovered hang gliding.

Now he spends his free time jumping off mountains with wings strapped to his back. He goes flying without his Flying Cloud.

The yacht waits.

She's a wonderful boat, but even Brown now realizes his goals for her were unrealistic. The keen edge of top-level ocean racing cuts too sharp and too costly for even the most ingenious amateur effort to pay off.

"Naturally I hoped she'd be a world-beater," said Brown, "but that was an optimistic and tentative hope."

From here on, he said, "I may sail an occasional Bermuda race and a few local Chesapeake races, but mostly I'll be cruising." b