UPS, Louisville and Muhammad Ali International Airport
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A moment of silence was held before Saturday night's game between No. 14 Louisville and California to honor victims of Tuesday's crash of a UPS cargo plane at Louisville Muhammad Ali International Airport.
The federal directive comes after two of three companies that operate the planes publicly announced they would ground their fleets.
The crash of a UPS plane in Louisville, Ky., has disrupted the shipper's air cargo headquarters, delaying some deliveries.
2don MSN
Investigators look into 'repeating bell' heard during takeoff of UPS cargo plane that crashed
Investigators say a repeating bell sounded as pilots tried to control a UPS cargo plane upon takeoff before it crashed in Louisville, Kentucky, this week.
In a statement released today, UPS officials provided additional information about the pilots who were killed in the Louisville flight crash.