Japan’s Nippon Cargo Airlines (NCA) returned the first of its freighters to service July 5, after its fleet was grounded for several days because of irregularities in maintenance records.

Checks on maintenance records were completed for the first freighter, a Boeing 747-8F, allowing it to resume operations between Tokyo Narita Airport and Shanghai Pudong International Airport. The remainder of the NCA freighter fleet “will resume in sequence as soon as aircraft safety is confirmed,” the carrier said.

NCA has 11 freighters, according to the Aviation Week fleet database. The total comprises eight leased 747-8s with an average age of 6.2 years, and three 747-400Fs with an average age of 10.4 years.

The carrier suspended all flights on June 17, after it discovered a discrepancy in maintenance records for one of its freighters. It decided to stop flying the other aircraft while it checked their records as well, out of “an abundance of caution.”

The discrepancy related to records about lubricating oil supply on a Boeing 747-8F in April. NCA has been under investigation by Japan’s Civil Aviation Bureau since May, because of the misreporting of two inflight incidents.

Adrian Schofield, avweekscho@gmail.com