MercoPress. South Atlantic News Agency

Boeings 777 grounded after incident when an engine caught fire and pieces fell over Denver

The US National Transportation and Safety Board (NTSB) is also investigating the incident, in which no one was hurt

Boeing has called for the grounding of 128 of its 777 planes across the world as US regulators investigated a United Airlines flight whose engine caught fire and fell apart over a suburban area of Denver in Colorado State.

United, South Korea's Asiana and Japan’s two main airlines - Japan Airlines (JAL) and All Nippon Airways (ANA) - confirmed they had already suspended operations of 63 planes fitted with the same family of engine which scattered debris over Denver on Saturday.

The US National Transportation and Safety Board (NTSB) is also investigating the incident, in which no one was hurt. Boeing warned that similarly fitted planes should be taken out of service until the US Federal Aviation Authority (FAA) had determined an inspection procedure.

“While the NTSB investigation is ongoing, we recommended suspending operations of the 69 in-service and 59 in-storage 777 aircraft powered by Pratt & Whitney 4000-112 engines,” Boeing said.

The announcements came after a United Airlines' Boeing-777 aircraft landed safely at Denver International Airport after its right engine failed. The incident on United Airlines Flight 328 from Denver to Honolulu took place shortly after it took off with 231 passengers and 10 crew members.

United said the next day it would voluntarily and temporarily remove its 24 active planes, hours before Boeing’s announcement. The 777-200s and 777-300s affected are older and less fuel efficient than newer models and most operators are phasing them out of their fleets.