Marine Corps resumes operation of Marineon choppers 2 years after crash SEOUL , June 9 ( Yonhap ) -- The Marine Corps has resumed the operation of its Marineon utility helicopters , two years after they were grounded after a deadly crash , officials said Tuesday . A MUH - 1 Marineon , the Marine variant of South Korea ' s KUH - 1 Surion helicopter , crashed in July 2018 , killing five service members . Defects in the rotor mast made by Airbus Helicopters were blamed for the accident . " The Marineon resumed flight operations Monday at the 1 st Marine Aviation Squadron in the city of Pohang , " an official said . The military authorities have fully implemented follow - up measures after the accident and carried out training for about 16 months in order to ensure their mission capabilities and safety , and experts decided on the resumption in April , he added . As part of such moves , the French government agreed last year to guarantee the quality of 13 major parts produced by Airbus for the Surion . The Marines received the choppers in January 2018 for the purpose of transporting its service members and equipment . The Marine Corps ' Marineon utility choppers are parked at an airfield of the 1 st Aviation Squadron in Pohang , North Gyeongsang Province , ahead of their operations resumption on June 8 , 2020 , in this photo provided by the military the following day . ( PHOTO NOT FOR SALE ) ( Yonhap ) graceoh @ yna . co . kr ( END )