evidence: Aug. 6 marks the anniversary of what has become known as the deadliest day for special operations in U.S. military history. On this date in 2011, a CH-47 Chinook helicopter crashed, call sign Extortion-17, killing 38 personnel on board. Among the casualties were 30 Americans, including 17 Navy SEALs. Bart, a military working dog, was also killed. [...] The final death toll included 15 members of SEAL Team 6; seven Afghan National Army Commandos; five U.S. Naval Special Warfare support personnel; three U.S. Army Reserve personnel from the 7th Battalion, 158th Aviation Regiment; two U.S. Navy SEALs from a West Coast-based SEAL team, two U.S. Army personnel from the 2nd Battalion, 135th Aviation Regiment, part of the Colorado Army National Guard; two U.S. Air Force pararescuemen from the 24th Special Tactics Squadron; one U.S. Air Force combat controller from the 24th Special Tactics Squadron; one Afghan civilian interpreter; and one U.S. military working dog. [...] Others have suggested that the attack was a pre-planned retaliation against SEAL Team 6 for their part in the mission that had taken down Osama bin Laden a few months earlier. Charlie Strange, the father of Petty Officer Michael Strange, a Navy cryptologist who was among those who died in the crash, stated that he was convinced the attack was an "inside job."