The FAA ordered United Airlines to conduct checks of Boeing 777 jets using Pratt & Whitney PW4000 engines before they operate further flights.
The engines are used on 128 planes globally which is about 10% of all Boeing 777s in operation.
It was prompted after a United Airlines engine failure caused debris to rain down across a wide area near Denver.
United is the only U.S. carrier which operates Boeing 777s with PW4000 engines.
It was revealed that Boeing had planned to replace engine covers before the incident.
According to the Wall St Journal, the plane maker and the FAA had been in talks over a potential fix after two earlier incidents.
Technicians are required to make a thermal acoustic image inspection of the fan blades on every engine, the FAA said.
Preliminary investigations by the National Transportation Safety Board points to metal fatigue of one or more fan blades.
"Based on the initial results as we receive them, as well as other data gained from the ongoing investigation, the FAA may revise this directive to set a new interval for this inspection or subsequent ones," the FAA said.
South Korea’s transport ministry ordered the grounding of Boeing 777s with PW4000 engines in line with Japan which did the same earlier this week.
Written by Ray Montgomery, US Editor
