The US Marine Corps is grounding 12 of its Marine Forces Reserve-operated Lockheed Martin KC-130T tanker/transports indefinitely, following a 10 July crash which left 16 service members dead.

An investigation into the fatal accident is ongoing, and the USMC will not comment on its potential root cause at this time. Its grounding order will not affect other variants of the C-130, the service confirms.

The destroyed KC-130T, “Yanky 72”, flew airlift missions with a team from the Marine Corps Forces Special Operations Command, based at Marine Corps Base Camp Lejeune, North Carolina. On 10 July, its crew had planned to fly from MCAS Cherry Point, North Carolina to Naval Air Facility El Centro, California, and then on to MCAS Yuma, Arizona. At about 4pm local time, air traffic controllers lost radar contact, and soon large plumes of smoke were seen near Itta Bena, Mississippi.

Early indications are that a problem occurred at cruise altitude, the USMC said following the accident. A large debris pattern was discovered at the crash site.

The KC-130T loss marked the deadliest USMC accident since 2005, when a Sikorsky CH-53E Super Stallion transport helicopter crashed in Iraq, killing 31 service members.