Original sentence: At 8:14, the pilot of Flight 11 failed to respond to an instruction to ascend from an FAA air traffic control (ATC) center in Boston.He was, at that time, flying opposite Boston arrivals, and as Flight 11 began to pose an air hazard, air traffic controllers began to move the arrivals underneath him
Edited sentence: At 8:14, the pilot of Flight 11 failed to respond to an instruction to ascend issued from the Boston Center, the FAA's Air Traffic Control (ATC) center.The pilot was, at that time, flying opposite Boston arrivals, and as Flight 11 began to pose an air hazard, air traffic controllers began to move the arrivals underneath him