Mike Tyson may be dethroned, but John F. Kennedy International Airport remains the heavyweight champion of air cargo.

The airport, the largest of three serving the New York metropolitan area, topped the world in air cargo handling in 1989, registering a record 1.36 million tons.That was an 6.7 percent increase from 1.3 million tons handled in 1988, according to figures released by the Port Authority of New York and New Jersey.

The port authority estimated cargo traversing the three airports was worth $91 billion.

Overall, New York's three airports, including JFK, La Guardia Airport and Newark International Airport, handled a record 1.89 million tons of cargo during 1988, said James E. Larsen, the port authority's manager for air cargo business development. That's up 4.7 percent from 1.8 million handled in 1988.

International cargo was more than half the volume for the three airports, reaching 1.1 million tons during 1989, up from 1 million tons the previous year. Domestic volume rose slightly to 804,691 tons from 779,778 tons, Mr. Larsen said.

While JFK remains the champion, Newark airport should experience a rise in cargo volume, said Hugh V. Bass, transportation manager for the international freight forwarding concern of F.W. Myers & Co. of Jamaica. N.Y.

Just last week, British Airways and Lufthansa German Airlines began operating from Newark, Mr. Larsen said. Scandinavian Airlines System began service at Newark in August, he added.

"We're talking to a few more international carriers," he said.

Lufthansa offers daily midday flights from Frankfurt and Hamburg, West Germany, to Newark and expects to inaugurate flights from Cologne on May 1, said Heidi Kapfenberger, a Lufthansa sales official.

Unfortunately, the Airbus Industrie A310 the German carrier uses on those flights into Newark doesn't offer much in the way of belly cargo space.

BA offers a daily flight between London and Newark, using 747s two days and L-1011s on the other five, said Mike Dwyer, the airline's quality controller for cargo.

Despite the upbeat forecasts, Newark's cargo volume declined in 1989, Mr. Larsen said. But this was due to the Eastern Airlines' machinists strike that crippled the carrier's operations at its Newark hub.

Overall, Newark's total cargo volume fell to 441,434 tons from 449,829 tons. Domestically, volume was way down, dropping to 388,812 tons from 413,900 tons.

On the international side, the start-up of SAS operations at Newark boosted overseas volume to 52,622 tons from 35,929 tons, Mr. Larsen said.

La Guardia airport totaled 63,504 tons during 1989, up slightly from 56,489 tons. Much of this volume was domestic, which rose to 59,592 tons from 52,667 tons. La Guardia has minimal international service and import-export cargo increased to 3,912 tons from 3,822 tons.