WASHINGTON, Jan 6 (Reuters) - The Federal Aviation Administration said Saturday it will order the temporary grounding of certain Boeing 737 MAX 9 airplanes after an Alaska Airlines flight on Friday was forced to perform an emergency landing following the loss of part of the fuselage.

FAA Administrator Mike Whitaker said the agency is requiring immediate inspections of certain planes before they can return to flight. The order impacts 171 airplanes worldwide. The emergency airworthiness directive will require operators to inspect aircraft before further flight that do not meet the inspection cycles. Required inspections will take around four to eight hours per aircraft. (Reporting by David Shepardson; Editing by Daniel Wallis)