Thailand's National Anti-Corruption Commission (NACC) has asked the Attorney General to prosecute a former deputy managing director of commercial affairs and former director of cargo and mail sales at Thai Airways International (TG, Bangkok Suvarnabhumi), alleging that they improperly paid certain operating expenses of Southern Air (Cincinnati International) during an ACMI cargo contract more than a decade ago.

The regulator argued that Phrit Buphakham and Poonsak Chumchuai's actions cost the airline USD10.6 million through their actions in 2009-2011. Their actions were criminal offences under the Act on Offences of Government Officials in Organisations or Agencies, the NACC allege. It forwarded its findings to the office of the Attorney General, urging to proceed with prosecution. It also told Thai Airways to "act in accordance with its duties."

The investigation revealed that Phrit and Poonsak approved the payment of landing and navigation fees for Southern Air flights by Thai Airways invoices, although the US carrier was contractually responsible for those expenses. Poonsak also allegedly informed Thai's finance team that Thai was responsible for the fees, knowing it was not, causing financial harm to the carrier.

At the time, Thai had a two-year block space purchase with Southern Air involving two B777-200LR freighters. That agreement ended in March 2011. Southern Air used to be an ACMI operator until it was acquired by and merged into Atlas Air (5Y, New York JFK) in 2021.

Phrit and Poonsak remain innocent pending the potential future court ruling.