AP/LM Otero
CNN reported that the pilot died during the flight.
The Airbus A320 jet with 152 passengers and crew on board landed safely with the co-pilot at the controls.
"American Airlines Flight 550, an Airbus A320, diverted to Syracuse Hancock International Airport (SYR) early this morning due to pilot illness," American Airlines said, in an emailed statement.
"Unfortunately, our pilot passed away. We are incredibly saddened by this event, and we are focused on caring for our pilot's family and colleagues."
AA Flight 550 took off from Phoenix Sky Harbor Airport last night at 11:55 pm local time and landed in Syracuse at 7:13 am Monday morning.
According to the Airline, a replacement crew was dispatched to get the passengers to Boston.