A rocket-propelled grenade fired by a Taliban fighter caused the Aug. 6 helicopter crash in Afghanistan that killed 30 U.S. special forces and military personnel, seven Afghan commandos, and a civilian interpreter, the Pentagon announced Wednesday.
The U.S. Central Command, based at MacDill Air Force Base in Tampa, Fla., concluded that the grenade was the “primary cause” of the crash of a North Atlantic Treaty Organization CH-47 Chinook helicopter in Wardak Province, according to a Defense Department news release.
The grenade hit “the aft rotor blade as the helicopter approached its combat landing zone,” according to the release. “There was no evidence of a pre-planned ambush.”
The incident was the biggest loss of U.S. troops in a single engagement since the start of the war 10 years ago.
The ill-fated mission targeted Qari Tahir, a Taliban leader in the Tangi Valley. He was killed by coalition forces the following month.
The initial assault force on Aug. 6 consisted of a U.S. Army Ranger platoon, an Afghan unit and a female cultural adviser. It was supported by two of the Chinook helicopters, made by Boeing Co., based in Chicago, two AH-64 Apache attack helicopters, an AC-130 aerial gunship and a “team” of surveillance and reconnaissance aircraft, according to an unclassified summary of the investigation that was released on the Central Command website.
The mission also included an Immediate Reaction Force built around a troop of Navy SEALs with the two Chinook helicopters, which returned to their base to refuel.
After the SEAL team was called for relief, a “decision was made to load all personnel on one aircraft” because the commander “wanted to mass troops quickly, and to mitigate the increased risk to a second helicopter approaching the landing zone,” according to the document.
The inquiry concluded that the decision to load the force on one helicopter to minimize its exposure to ground fire and mass the troops “was tactically sound.”
After the Chinook carrying the SEALs descended to about 100 to 150 feet above the ground and slowed to about 58 miles per hour, a “previously undetected group of suspected Taliban fighters fired two or three RPGs,” rocket-propelled grenades, “in rapid succession from the tower of a two-story mud-brick building” about 220 meters south of the Chinook, according to the summary.
The first round missed the helicopter and the second struck and exploded, taking out about 10 feet of the rotor blade, the document states.
“Within a matter of seconds, while the aircraft spun violently, the aft, then forward rotor blade systems separated from the aircraft, and the main fuselage dropped vertically into a dry creek bed. The airframe was immediately engulfed in a fireball, causing multiple secondary explosions of fuel and munitions until the aircraft burned out several hours later,” according to the summary.
Seventeen of the Americans killed were U.S. Navy SEALs, most from the elite force once known as SEAL Team Six that carried out the May 2 raid that killed al-Qaeda leader Osama bin Laden in Abbottabad, Pakistan. None of those killed were from the unit involved in the bin Laden raid.
A full copy of the redacted report will be made available on the site after a final briefing of the findings, scheduled for Thursday afternoon, according to the release.
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