On September 4, 1971, the aircraft operating the flight crashed into a mountain in Haines Borough, about 18 miles west of Juneau, Alaska, while on approach for landing.

[3] The NTSB determined that the aircraft and engines were properly maintained and in good working order at the time of the accident.

The flight departed ANC on time at 9:13 a.m. and the first stop at CDV was uneventful, apart from a minor issue with a cargo door which caused a short delay.

[5]: 3 At 11:46 the crew contacted Anchorage air traffic control and reported they were at Flight Level 230 (FL230 or 23,000 feet [7,010 m]), 65 miles (56 nmi; 105 km) east of Yakutat.

The controller then gave them the current altimeter setting at JNU and requested they report passing 11,000 feet in the descent.

[5]: 3 At 11:54 the controller instructed the crew to stop their descent at 12,000 feet and changed the clearance limit to PLEASANT intersection where they could expect to hold.

The controller then cleared the flight for the straight-in LDA approach to Runway 8 and instructed them to cross HOWARD inbound at or below 9,000 feet (2,743 m).

Vertical guidance was provided by instructions on the approach chart; the procedure involved descending to various published altitudes upon crossing specific intersections between the localizer and a nearby VOR station.

The tower controller replied, "Alaska 66, understand...I didn't copy the intersection...," and continued his transmission, giving them the current weather conditions and runway in use, and asked them to report over BARLOW.

[5]: 4 At approximately 12:15 the aircraft struck the eastern slope of a canyon in the Chilkat Range of the Tongass National Forest at the 2,500-foot (760 m) level, 18.5 miles (16 nmi; 30 km) west of Juneau.

When the crew stopped responding, JNU tower notified local authorities in Juneau, who immediately began a search for the aircraft.

A few hours later, the wreckage was located on the eastern slope of the Chilkat ridge, west of Juneau airport at the coordinates 58°21′42″N 135°10′12″W / 58.36167°N 135.17000°W / 58.36167; -135.17000.

[5]: 4–5 [7] Two witnesses in the area of the Chilkat Mountains stated that they heard a low-flying jet aircraft, but could not see it because of clouds and low visibility, which they estimated at 200–300 feet (61–91 m).

After determining that there were no apparent issues with the crew's qualifications or the aircraft, their investigation focused on the navigational equipment and techniques used for the approach.

In addition the NTSB found there was potentially a lack of crew coordination between the two pilots in their navigation radio tuning procedures.

Interestingly, this type of problem is used as a plot device in famed aviation writer Ernest K. Gann's 1973 novel Band of Brothers.

[8] In the book, a Boeing 727 crashes after receiving false navigational information as a result of military radio jamming.