AINonline.com--Continued weakness in cargo markets and stubbornly high fuel prices have convinced FedEx to retire 18 Airbus A310-200s and 26 related engines permanently, along with six Boeing MD-10-10s and 17 associated engines, the company announced last Monday. The Memphis, Tennessee-based cargo giant noted that it has already grounded most of the airplanes and recorded a $134 million charge during its fourth quarter to reflect the retirements. Read more!