A US Airways plane's luggage sits on the tarmac as another plane comes in for a landing at Philadelphia International Airport Friday, Aug. 5, 2011 in Philadelphia. Passengers aboard the flight that ... more 
A US Airways plane's luggage sits on the tarmac as another plane comes in for a landing at Philadelphia International Airport Friday, Aug. 5, 2011 in Philadelphia. Passengers aboard the flight that arrived from Scotland were removed from the plane because of an unspecified threat Friday, and the plane was taken to another part of Philadelphia International Airport to be inspected. (AP Photo/Alex Brandon) less 
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Associated Press | Photo By Alex Brandon
Fri, Aug 5, 2011 6:49 PM EDT