Boeing’s (BA) long, difficult year kicked off with a 737 Max door plug blowout, and now a new part is drawing scrutiny from federal investigators. Reuters reports that the Federal Aviation Administration is looking into problems with the planes’ engines after a pair of bird strikes last year aboard a pair of Southwest Airlines (LUV) flights.

U.S. aviation regulators are examining whether pilots of Boeing Co.’s 737 Max should take new precautions following two incidents in which planes were filled with smoke after large