A training accident that killed nine soldiers late last month involved two Black Hawk helicopters colliding in midair, a preliminary report confirmed.
"While conducting night training in a military operations area/special use airspace, two HH-60 aircraft collided midair," the Army Combat Readiness Center said in a Preliminary Loss Report.
Officials had previously not specified the nature of the incident, one of the deadliest training accidents in Army history, beyond saying the two Black Hawks were involved during training out of Fort Campbell, Kentucky.
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A team from the Alabama-based center, which probes all fatal Army accidents, is continuing to investigate, according to the preliminary report. Questions such as whether the crash was caused by pilot error, mechanical failure or other issues were not addressed in the initial two-paragraph report.
Investigators have recovered the flight recorders, also known as black boxes, from the helicopters and are analyzing them, officials previously said.
"We cannot provide a timeline as to when the investigation will be completed," Lt. Col. Tony Hoefler, spokesman for the 101st Airborne Division (Air Assault), said in a news release last week announcing the recovery of the black boxes. "The duration of the investigation is determined by the thorough analysis of all factors."
On the night of March 29, a pair of medical evacuation Black Hawks from the 101st Airborne Division were conducting routine training, with the pilots wearing night vision devices, when the accident happened. None of the soldiers aboard the helicopters survived.
The Army has identified the soldiers as Warrant Officer 1 Jeffery Barnes, 33; Cpl. Emilie Marie Eve Bolanos, 23; Chief Warrant Officer 2 Zachary Esparza, 36; Sgt. Isaacjohn Gayo, 27; Staff Sgt. Joshua C. Gore, 25; Warrant Officer 1 Aaron Healy, 32; Staff Sgt. Taylor Mitchell, 30; Chief Warrant Officer 2 Rusten Smith, 32; and Sgt. David Solinas Jr., 23.
The accident is the 101st Airborne's deadliest incident since a 1988 crash that also involved a pair of Black Hawks and killed 17 soldiers. In the 1988 incident, investigators concluded that one Black Hawk slammed into another mid-air while conducting a routine maneuver.
An average of five soldiers per year have died in on-duty aviation accidents since 2018, according to the Army Combat Readiness Center. The Fort Campbell incident is the Army's fourth "Class A mishap" -- defined as an accident in which there's more than $2.5 million worth of property damage, the aircraft is entirely destroyed, or someone dies or is permanently disabled -- this year, bringing the number to one more than the same time last year.
-- Rebecca Kheel can be reached at rebecca.kheel@military.com. Follow her on Twitter @reporterkheel.
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