Hughes Airwest Flight 706 - Investigation

Investigation

The stricken airliner crashed onto Mount Bliss in the San Gabriel Mountains at an elevation of approximately 3,000 feet (910 m), where the bulk of the wreckage landed in a gorge. Fire department officials sent search and rescue helicopters to the crash site, but efforts were hampered by thick fog. Nine bodies were initially found at the crash site, a number of them intact and still strapped into their seats. News reports indicated that these bodies had apparently been thrown clear on impact, and had come to rest alongside the tail section of the aircraft.

Some eyewitnesses reported that the F-4B's left wing impacted the center of the airliner's fuselage immediately after performing a barrel roll. Other witnesses claimed that the F-4B ripped a large hole in the fuselage of the DC-9, through which papers and luggage streamed as the crippled airliner fell. Though papers with the words "Air West" and the date of June 6 were collected by Sheriff's deputies, no luggage was recovered.

The National Transportation Safety Board (NTSB) investigated the incident, assisted by the Marine Corps, Federal Aviation Administration (FAA), Hughes Airwest, and the Airline Pilots Association. Early statements released by the NTSB revealed that the F-4B fighter had attempted to swerve away from the DC-9 immediately prior to impact, and that an additional 10 feet of clearance would have averted the entire collision. Additionally, the NTSB confirmed that the fighter had impacted the DC-9 in two places, with its left wing impacting the airliner's forward passenger cabin and the vertical stabilizer "slicing through" the cockpit.

The DC-9 carried a primitive flight data recorder that recorded basic information about the aircraft's air speed, acceleration, heading, and altitude on metal foil tapes. Additionally, the aircraft was equipped with a simple cockpit voice recorder that recorded all conversations that took place in the cockpit of the aircraft. The flight recorder was recovered by investigators on Thursday, June 10, 1971, and sent to Washington D.C. for analysis. Though the voice recorder was also recovered, the thermal protective measures had failed and the recording tapes were destroyed by fire.