2011 Chinook shootdown in Afghanistan

On 6 August 2011, a U.S. Boeing CH-47 Chinook military helicopter, call sign Extortion 17, was shot down while transporting a quick reaction force attempting to reinforce an engaged unit of Army Rangers in Wardak province, west of Kabul, Afghanistan. The resulting crash killed all 38 people on board—25 American special operations personnel, five United States Army National Guard and Army Reserve crewmen, seven Afghan commandos, and one Afghan interpreter—as well as a U.S. military working dog. It is considered the worst loss of U.S Military life in the Afghanistan campaign, surpassing Operation Red Wings in 2005.

Deaths
The deaths included:
 * 15 U.S. Navy SEALs from the Naval Special Warfare Development Group's Gold Squadron
 * 7 Afghan National Army Commandos, part of Afghan National Army
 * 5 U.S. Naval Special Warfare support personnel.
 * 3 U.S. Army personnel from the 7th Battalion, 158th Aviation Regiment
 * 2 U.S. Navy SEALs from a west coast based SEAL team.
 * 2 U.S. Army personnel from the 2nd Battalion, 135th Aviation Regiment, part of Colorado Army National Guard
 * 2 U.S. Air Force Pararescuemen from the 24th Special Tactics Squadron
 * 1 U.S. Air Force Combat Controller from the 24th Special Tactics Squadron
 * 1 Afghan civilian interpreter
 * 1 U.S. Military Working Dog

The 30 American deaths represent the greatest loss of U.S. military lives in a single incident in the decade-long war in Afghanistan that began in 2001.

Blow to U.S. Special Operations Forces
Of the Navy SEALs that were killed 15 were members of the Naval Special Warfare Development Group (DEVGRU), also known as SEAL Team Six. This unit is also known for having carried out the Operation Neptune Spear, which resulted in the killing of Osama Bin Laden; however, none of the SEALs killed participated in the operation. The other two Navy SEALs killed in the helicopter shootdown were from a West Coast-based SEAL unit. The five other Navy personnel were NSW support personnel. In addition to the NSW losses, three AFSOC operators died in the crash, one Combat Controller and two Pararescuemen, all members of the 24th Special Tactics Squadron. Their deaths are the greatest single loss of life ever suffered by the U.S. Special Operations community in the 24-year history of the U.S. Special Operations Command.

A source from the Navy's special operations community described the reaction as, "Shock and disbelief. There's no precedent for this. It's the worst day in our history by a mile." The previous highest U.S. death toll from a single incident in the war also came from a rocket attack on a Chinook helicopter carrying Navy SEALs during Operation Red Wings on 28 June 2005. In that incident sixteen Navy SEALs and Army special operations troops were killed and three more SEALs were killed in fighting on the ground.

Initial accounts
The U.S. military helicopter carrying special operations forces to a night-raid in the Tangi Valley of Wardak Province, was most likely brought down by a rocket-propelled grenade, according to military officials.

General Abdul Qayum, the police chief of Wardak, said the military helicopter was shot down around 1 am Saturday after a U.S. night assault on a house in the village of Jaw-e-Mekh Zareen in the Tangi Valley that had lasted at least two hours. Local witnesses reported that at least two helicopters had taken part in the U.S. special forces attack on the compound, killing eight Afghan insurgents, but that just after the helicopter had taken off again it was fired upon from a separate position. Shahidullah Shahid, a spokesman for the provincial governor, said: "The US chopper that crashed last night was shot down by the Taliban as it was taking off. A rocket fired by the insurgents hit it and completely destroyed it."

A spokesman for the Taliban, Zabiullah Mujahid, confirmed that eight of the movement's fighters had been killed in the assault on the compound. He said: "They wanted to attack our Mujahideen who were in a house, but our Mujahideen resisted and destroyed a helicopter with a rocket-propelled grenade."

Later accounts
Subsequent reports stated that the U.S. military helicopter had been delivering reinforcements to U.S. Army Rangers, another special operations unit, when their night raid on a compound to kill or capture a senior Taliban leader went awry. During the battle US forces observed a small group of Taliban trying to flee the scene. The group probably contained the commander and a few of his bodyguards while the remaining Taliban fighters offered resistance in an effort to buy the group enough time to escape. In order to prevent this US forces called in for support.

Other reports alleged that the Taliban had laid an elaborate trap for U.S. special operations forces, luring them in with false information. A senior Afghan government official, speaking anonymously, said that Taliban commander Qari Tahir had fed U.S. forces false information about a meeting of insurgent leaders and fighters waited for the helicopter from both sides of a steep valley: "The Taliban knew which route the helicopter would take. That's the only route, so they took position on either side of the valley on mountains and as the helicopter approached, they attacked it with rockets and other modern weapons. It was brought down by multiple shots."

In October 2011, US Central Command (CENTCOM) announced that an investigation carried out following the shoot down concluded "that all operational decisions, linked to the incident, were deemed tactically sound". The article states that the helicopter crashed after a RPG round impacted the aft rotor assembly.

Subsequent events
On 10 August 2011, the U.S. military claimed that the insurgent who fired the rocket-propelled grenade had been killed only two days afterward in a F-16 airstrike, saying only that intelligence gained on the ground provided "a high degree of confidence" that the person was among those killed in the airstrike from two days earlier, but providing no other details.

During the same Pentagon news conference in which he announced that the F-16 airstrike had taken out "less than 10" of the insurgents involved, International Security Assistance Force (ISAF) commander in Afghanistan John R. Allen said the military investigation into the helicopter downing would also review whether small arms fire or other causes might have contributed to the downing.

Many of the men interviewed for the book Fearless: The Undaunted Courage and Ultimate Sacrifice of Navy SEAL Team SIX Operator Adam Brown by Eric Blehm perished in the crash.

In 2013 Jason Chaffetz said he would hold an investigation of the United States House Oversight Subcommittee on National Security into the matter.