What was found
FLT 1081, BOS-RIC. AIRCRAFT PERFORMED AN AIR TURN BACK TO BOS, PAX DOOR FWD OPEN MASTER CAUTION AT 7000MSL. RAN QRH. SEVERAL MINUTES LATER F1 REPORTS VIBRATION AND NOISE FROM DOOR L1 NOT PREVIOUSLY HEARD INCREASING TO SIGNIFICANT. L1 DOOR DEFLECTOR, OPEN