Two fiber glass boats from New Zealand are making waves at the 12-meter world championships off Perth, Australia.

Three races into the seven-race regatta, New Zealand entries KZ 5 and KZ 3 are second and fifth out of 14 boats, and in the best company. The leader is Australia III, defending America's Cup-holder Alan Bond's new boat. In third place is America II, the New York Yacht Club entry, and in fourth is Bond's 1983 Cup champion Australia II.

The world championships are preliminaries to next year's America's Cup regatta off Perth, the first Cup competition to be held outside the United States since the yacht America won sailing's top prize off England in 1851.

New Zealand's early success is intriguing for two reasons: First, the country never before has had an entry in the America's Cup; second, the New Zealanders are using the first fiber glass 12-meters ever approved for Cup competition, and everyone wants to see how plastic fares against traditional aluminum boats.

The New Zealand 12s were designed by the team of Bruce Farr, Lawrie Davidson and Ron Holland. Farr, a New Zealander with offices in Annapolis, is just back from Australia, where he watched preliminary racing. He is not dancing in the aisles yet, but he is pleased.

"Our boats could clearly hang in with anything there," Farr said, "and our crews have done only 30 to 40 hours of sailing. We're very pleased to be competitive after jumping into the deep end with no real experience."

Farr said his team chose fiber glass for two reasons: It felt the material could be made stiffer, resulting in less flexing than aluminum in the rough seas off Perth, and since it owned no trial horse it needed two boats quickly, to work one against the other. With glass, once a wooden mold was made the team could form two identical hulls quickly and inexpensively, Farr said.

Farr said conditions off Perth were just about as expected exactly a year before the Cup finals are to get under way. Afternoon winds ranged up to 30 knots and seas were heavy and unpredictable.

A second surprise in the world championships has been the performance of French Kiss, an unheralded entry from France that won the second race of the regatta and has shown remarkable speed, Farr said. True North, the new Canadian entry, also sailed well, he said.

Significantly absent from the competition is Dennis Conner's Sail America team, operating in secrecy in Hawaii. Conner, the 1980 Cup champion and loser in 1983, has three new boats in the water and said he didn't want to waste time shipping his team and a boat or two to Perth.

The America II team is sailing its backup boat, U.S. 42, the first 12-meter it built in its three-boat effort to restore the Cup to the United States. Farr said America II looks in racing "just like the well-oiled machine it is."

Also absent is the Australian boat Kookaburra, designed and skippered by Iain Murray and rumored to be "so fast they don't want to give anything away by racing," said Farr. "That may be true," he said, "and then again, they may be just using that as a publicity stunt to raise money."

Racing will continue through the weekend.