A senior United States Air Force official has warned that Boeing must resolve persistent technical issues with its KC-46 aerial refueling tanker before it will consider further orders for the aircraft. The issue is related to the Boeing KC-47 Pegasus, a tanker developed by Boeing to replace the Boeing's KC-135 Stratotanker fleet. The tanker has been plagued by delays, engineering challenges, and billions of dollars in financial losses. The Air Force has ordered 183 aircraft under its existing procurement plan, with over one hundred already delivered and entering operational service. However, the service remains cautious about expanding the fleet until the manufacturer demonstrates that the most persistent issues have been resolved. The program has become one of the most expensive fixed-price defense contracts in Boeing's history and has incurred over seven billion dollars in charges related to development overruns, redesign work, and production complications.