USPS OIG Audit: Air Mail Not Moving as Assigned "The U.S. Postal Service spent about $3 billion to transport mail via air in fiscal year (FY) 2021, an increase of about $53 million over FY 2020. These costs consisted of contracted services from [redacted], commercial airlines, [redacted] , auxiliary transportation, supplemental ad hoc charters, and terminal handling services (THS) operations."