WASHINGTON, Aug. 16, 2006 – Two Massachusetts Air National Guard F-15 fighter jets scrambled today to escort a Washington-bound United Airlines flight to Boston’s Logan National Airport, a U.S. North American Aerospace Defense Command spokesman confirmed. NORAD ordered the unit to scramble the aircraft, based at Otis Air National Guard Base, Mass., after receiving a “domestic event network call” on the aviation security hotline that links the command to the Department of Homeland Security and other U.S. aviation security organizations, Mike Kucherak said. The call followed an incident aboard United Airlines Flight 923, originally scheduled to fly from London Heathrow...