On 13 December 2017, a 7.7-kilogram window fell from a USMC CH-53E “Super Stallion” helicopter onto the grounds of the Futenma Dai 2 Elementary School, Ginowan City. Although the US military soon apologized and admitted the cause of the accident was human error, it has never made public any details.
Now, via the US Freedom of Information Act, Okinawa Times has obtained an inquiry produced by the Marine Corps two days after the accident. The report describes what happened in the skies above the school that day, including two key revelations: the presence of a general and his entourage of VIPs may have distracted the pilots from completing thorough preflight checks, and a lack of recognition from the USMC that the window’s impact site was an elementary school.
According to the 34-page report, two pilots – a commander and a second pilot – boarded the Super Stallion on the morning of 13 December at MCAS Futenma, Ginowan City. While the second pilot was preparing the aircraft for pre-taxi checks, the commander exited the cockpit to meet a general who was traveling with a group of ten VIPs. This left the second pilot to conduct checks alone, including confirmation the window next to her seat was correctly closed.
Upon arrival at the aircraft, the general was given an intercom-fitted helmet and strapped into a gunner’s belt at the front of the cabin; the other VIPs were escorted to the rear.
With the second pilot at the controls, the Super Stallion took off and then, at a height of approximately 230 meters, it started a left turn. At this moment, the pilots heard a loud noise and felt a rush of air in the cockpit. The second pilot noticed that the window next to her had opened, then it dropped from the helicopter. She “was unable to grab it because she would have had to let go of the sticks and lose control of aircraft,” recounted one Marine.
Another crew member described what happened to the window. “They reported over ICS [intercommunications system] that it landed in a playground field with approximately 30 children in it. The general who was up ICS then said we needed to return to base land [sic] and recover the window as soon as possible.”
With the commander now at the controls, the Super Stallion made an emergency landing at MCAS Futenma. Marines were ordered to replace the window immediately so the VIPs could continue their journey in the same aircraft, but, according to the report, the general and his entourage departed. Despite the general’s involvement in several aspects of the incident, the USMC inquiry does not contain a statement from him or any of the other ten VIPs.
The inquiry blamed the accident on two main factors: (1) before take-off, the pilots and aircrew had not checked that the window’s emergency release handle was correctly fitted with a safety wire; (2) during the flight, the handle “was inadvertently manipulated” causing the window to fall. In recommendations, the Commanding Officer of the Marine Aircraft Group 36 ordered that, “a thorough dual concurrent inspection will be conducted prior to any flight”. The comment appears to address the commander’s absence from the cockpit to meet the general, leaving the second pilot alone to conduct pre-taxi checks.
The full FOIA-released report can be downloaded here.
Moreover, in the accident report, there is one significant omission: it fails to mention that the window struck a school.
In statements to the accident investigators, Marines on board the Super Stallion and those who witnessed the accident from MCAS Futenma referred to the impact site as “a field” or “soccer field.” Even the investigators’ summary, produced the day after the drop, asserts the window landed in “the open dirt field, located just to the North of the MCAS Futenma.
By the time this summary was written, the fact that the window had landed in an elementary school had been widely reported; the investigation itself included a link to a TV news report which featured the school prominently in its coverage.
Okinawa Times has contacted USMC and United States Forces Japan for comment on why the inquiry avoids mentioning the school, and whether Marines stationed at MCAS Futenma are informed that Futenma Dai 2 Elementary School, and other schools and hospitals, are located nearby.
Reacting to the revelations in the USMC enquiry, Okinawa Governor Tamaki Denny, stated "It was a very shocking accident, and now there is new information about the lack of thorough management. Therefore, I would like to reiterate that [the US military] must thoroughly maintain and manage its aircraft to prevent such a reoccurrence.
MCAS Futenma has been dubbed the most dangerous base in the world because, located in the center of Ginowan City, it is surrounded by homes, schools, and public facilities. In August 2004, a USMC CH-53D “Sea Stallion” helicopter from MCAS Futenma crashed onto the campus of the adjacent Okinawa International University.
In response to the window drop in 2017, Okinawa Prefecture demanded the end to flights over the Futenma Dai 2 Elementary School – but the USMC has not complied. In 2018, the Japanese government paid for shelters to be constructed on the school’s grounds where students could evacuate during flyovers.