A C-130J Super Hercules aircraft sits on the flight line at Ramstein Air Base, Germany, Sept. 18, 2020. A $21-million accident involving a C-130 Hercules assigned to Ramstein in April was caused by pilot error prior to landing, the Air Force said Feb. 16, 2021. (Kirby Turbak/U.S. Air Force)

Pilot error caused $21 million in damage to an Air Force cargo plane that landed hard during a training flight at Ramstein Air Base in April, the service said following the release of an accident investigation board’s findings.

The C-130J Super Hercules pilot reduced power to the engines 70 feet above the ground and fully idled them at 45 feet, an Air Force statement said Tuesday. That caused the plane to drop down onto the runway too quickly, the statement said.

The pilot, who was simulating a landing on a dirt airstrip, known as a maximum effort landing, should have started to pull the power at about 20 feet in order to land “in the center of the runway touchdown zone,” the report said.

A reduction in thrust accelerates the “sink rate” of the C-130J and leaves the aircraft’s propellers unable to generate high-velocity airflow over the wings, the report said.

The accident caused no significant injuries or damage to civilian property, the investigation report said. The aircraft was assigned to the 37th Airlift Squadron, based at Ramstein.

The failure by both the pilot and the aircraft commander, who was also the instructor pilot, to identify and stop “the excessive sink rate … in a timely manner were substantially contributing factors” to the accident, the statement said.

The landing caused significant damage to the center wing, both outer wings, the left and right main landing gear assemblies and engines, including the mounting structures, the report said. Visible damage to the plane included a buckled lower fuselage, pulled rivets and cracked sealant, images included in the report showed.

Although the investigation board found no evidence that the operations tempo contributed to the accident, the pilot noted that one of two sorties he planned to prepare him for the April 23 evaluation flight was canceled due to coronavirus restrictions at the time.

The report noted that the squadron’s high operations tempo, supporting both U.S. Air Forces in Europe and Air Forces Africa missions, leaves less time for local training missions, which are particularly important for less experienced air crews.

“The lack of local training sorties, combined with local area restrictions, make it difficult to practice critical combat airlift skills, to include maximum effort takeoffs, approaches, and landings,” the report said.

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