Pilot error caused military plane crash that killed 9 near Savannah, authorities say

Pilot error has been ruled as the cause of a military plane crash that killed nine people outside Savannah in May, according to a report by the U.S. Air Force Accident Investigation Board.

The report, which was released Friday, cited several errors made by multiple crew members that led to an inoperative engine, a left wing stalling and the plane eventually nosediving onto Ga. 21 shortly after takeoff from Savannah/Hilton Head International Airport on May 2.

The nine people killed were airmen in the Puerto Rico National Guard.

The Lockheed WC-130 Hercules was assigned to the 156th Airlift Wing, which is based out of Muñiz Air National Guard Base. The plane, which was more than 60 years old, was making its final trip to Davis-Monthan Air Force Base in Arizona for retirement.

MORE: 60-year-old military plane was on retirement flight when it crashed

"The purpose of the investigation was to identify the cause and contributing factors that led to this tragic and unfortunate incident,” Accident Investigation Board team leader Brig. Gen. John C. Millard told Channel 2 Action News. "By conducting a thorough review and investigation, we hope to provide answers to the families of brave airmen that lost their lives and prevent future occurrences and tragedies."

Millard’s team spent about a month reviewing an array of evidence, including interviews, logs, video, briefing material and inspection of aircraft wreckage, Channel 2 reported.

RELATED: Horrifying photos of the military plane crash

The left, outermost engine experienced problems and did not provide normal revolutions per minute (RPM), causing the engine’s torque to be “significantly decayed,” substantially lowering the engine’s thrust, the report said.

The crew didn’t recognize the performance delay, and the plane narrowly took off before the runway ended.

While the plane’s landing gear was being retracted, the crew noticed the malfunction and shut down the engine, the report said.

However, they failed to follow certain procedures, meaning the plane’s flaps remained at 50 percent. This, combined with a crew member banking left into the inoperative engine, caused the plane to continue to climb until the left wing stalled, the report said. As a result, the plane began its nosedive onto the interstate.

The men aboard included: pilot José Rafael Román Rosado, Maj. Carlos Pérez Serra, 1st Lt. David Albandoz, Senior Master Sgt. Jan Paravisini, Master Sgt. Jean Audriffred, Master Sgt. Mario Braña, Master Sgt. Víctor Colón, Master Sgt. Eric Circuns and Senior Airman Roberto Espada.

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