A 65-year-old man accused of slapping and punching a Delta Air Lines flight attendant on a flight from Narita to Honolulu pleaded guilty to misdemeanor assault this morning in federal court and is scheduled to return to Japan this afternoon.

Sohei Yamanouchi, a Japanese citizen, was fined $2,500.

FBI agents here arrested Yamanouchi about 7:30 a.m. Monday following the arrival of Delta Flight 608. The incident took place in the business class section of the aircraft, the FBI said.

He was released Monday afternoon on signature bond to attend his son’s wedding here Tuesday.