@CNN: Boeing has been here before. In the 1960s, four new Boeing 727 jets crashed within a four-month period: https://t.co/yg5OHWud1e https://t.co/HDOcHiprn8

@CNN: Boeing has been here before.

In the 1960s, four new Boeing 727 jets crashed within a four-month period: https://t.co/yg5OHWud1e https://t.co/HDOcHiprn8