As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#647, BOS- SLC. (AIRCRAFT PERFORMED AN AIR TURN BACK TO BOS AND DECLARED AN EMERGENCY) ' HYD "G" RSVR LO LVL; REPLACED LDG DOOR ACTUATOR LINE FWD DUE TO BEING RUPTURE IAW AMM 32-31-49-400-001-A, ALSO SERVICES GREEN HYD TO SPECIFICATION IAW AMM 12-12-29. NO DEFECT/LEAKS NOTED AT THIS TIME.