Pilot error led to the fatal crash of a TU-2S aircraft, the two-seat training version of a U-2 Dragon Lady spy plane, about 20 miles west of Beale Air Force Base, California, on Sept. 20, 2016, according to an Air Combat Command Accident Investigation Board report released Tuesday.

When the plane, assigned to the 9th Reconnaissance Wing at Beale stalled during a training maneuver, the two pilots ejected, but during the ejection sequence, Lt. Col. Ira S. Eadie, the instructor pilot, was killed. The other pilot received minor injuries.

ADDS CONDITION OF PILOTS - The wreckage of a U-2 spy plane that crashed after taking off from Beale Air Force Base on a training mission in Northern California, is seen Tuesday, Sept. 20, 2016. The U.S. Air Force says one pilot was killed, and one was injured after they ejected from the plane. (Hector Amezcua/The Sacramento Bee via AP)
ADDS CONDITION OF PILOTS - The wreckage of a U-2 spy plane that crashed after taking off from Beale Air Force Base on a training mission in Northern California, is seen Tuesday, Sept. 20, 2016. The U.S. Air Force says one pilot was killed, and one was injured after they ejected from the plane. (Hector Amezcua/The Sacramento Bee via AP)

The wreckage of a TU-2S is strewn across the foothills south of the Sutter Buttes mountain range in Northern California. The training aircraft crashed after taking off from Beale Air Force Base on Sept. 20, 2016.

Photo Credit: Hector Amezcua/The Sacramento Bee via AP

"The purpose of this report was to identify the causes and contributing factors which may have contributed to the incident," said Brig. Gen. David S. Nahom, AIB board president, in an ACC news release. "This was a terrible tragedy, and our heartfelt condolences go out to Lt. Col. Eadie's family."

U-2 pilots are competitively selected from the Air Force's pool of qualified aviators. As part of their interview process, applicants take part in three so-called "acceptance flights" under the supervision of a TU-2S instructor pilot.

The mishap occurred during the first acceptance flight for the interviewing pilot. The pilot was conducting "approach to stall" training, which emphasizes recognition of approaching stall conditions and the procedures used to recover the aircraft to normal flight.

During the recovery from the stall, however, the interviewing pilot’s flight control inputs placed the aircraft into an unintentional secondary stall, which led to a sharp left wing drop and excessive nose-low attitude.

As the aircraft approached an inverted position and neared the minimum uncontrolled flight ejection altiutude, the instructor pilot commanded ejection.

"During the ejection sequence, the instructor pilot and his ejection seat struck the aircraft’s right wing resulting in fatal injuries," according to the news release.

The aircraft was completely destroyed, at a loss of approximately $32 million, the release stated.