A former Cuban Air Force pilot who defected to the United States almost two years ago in his MIG jet flew back to Cuba on Saturday night, landing a small plane in traffic along a coastal highway and quickly picking up his wife and two sons from the roadside before turning back to Florida.

In an interview yesterday, the pilot, Orestes Lorenzo Perez, said he flew low over the roof of a car and landed the aging Cessna in the path of an oncoming truck. The truck driver hit his brakes and managed to stop just 10 yards from his propeller blades. Mr. Lorenzo said he then turned his plane around, picked up his family and took off again for Florida in the rosy twilight of the Cuban sunset.

"I'm thrilled that my family is back in freedom with me now," Mr. Lorenzo said.

Mr. Lorenzo said he believed that his low-altitude flight south across the Florida Straits, most of which he made at wave-skipping altitudes, went undetected by the Cuban authorities until it was too late for any attempt to stop him. American officials said they were unsure whether radar operated by the Customs Service or any other agency picked up the flight.

"We're looking into that to see if we did what we're supposed to do, but I don't have any data on it so far," said Tom Bowers, a spokesman for the main Customs Service radar and intelligence center in Dade County, Fla. The center suffered damage in Hurricane Andrew in August and is still being repaired, Mr. Bowers said. Special Status for Exiles