Alaska Airlines Flight 779

Alaska Airlines — Flight 779

Alaska Airlines Flight 779, a Military Air Transport Service (MATS) charter originating at Paine Field and stopping at Travis AFB and Anchorage, was carrying 25,999 pounds of cargo to Tachikawa, Japan. It crashed 200 feet short of the runway at Shemya Air Force Base during a Ground Controlled Approach (GCA) in heavy fog. The investigation determined that critical airfield lighting, including the red approach lights and the first four pairs of runway lights, were inoperative at the time of the accident. The flight crew was never notified of these deficiencies during their stop in Anchorage, and the GCA controller failed to provide positive guidance when the aircraft drifted below the glidepath during the final stages of the approach.

Aircraft

Douglas DC-6A

Registration

N6118C

Phase

Cause

Souls on Board

Fatalities

Origin → Dest

Paine Field, Everett, WA → Shemya Air Force Base, Alaska

Report

Investigation Summary

Flight 779 was transporting 25,999 pounds of military cargo from Travis Air Force Base to Tachikawa, Japan, with a scheduled refueling stop at Shemya. During the approach to Runway 10, the aircraft was operating under GCA guidance due to a 200-foot ceiling and restricted visibility in fog. Radar contact was established 18 miles out at 5,500 feet. As the aircraft neared the threshold, the GCA controller observed it slipping below the ideal glidepath. At two miles out, the aircraft was 10 to 25 feet low; at one mile, it was 30 to 40 feet low. Although the controller advised the crew to 'ease the aircraft up,' the crew did not correct the descent. The controller later stated he assumed the pilots had transitioned to a visual approach when the aircraft began to descend more rapidly. However, the lack of functional approach and threshold lighting likely deprived the crew of the visual cues necessary to judge their height above the terrain, leading to the impact 200 feet short of the runway.

Final Conclusions

The Civil Aeronautics Board (CAB) determined the probable cause was the absence of approach and runway lights, combined with the failure of the GCA controller to provide more positive guidance to the pilot during the final stages of the approach. The board noted that the lighting deficiencies were not reported to the crew at Anchorage or during the approach, and the GCA transmissions were not recorded, in violation of standing instructions.

Photographic Evidence (1)

Everts Air Cargo

Video Analysis

No video analysis linked for this case file yet.

Airframe & Maintenance

Airframe Hours

10,600

Last Major Check

146 hours prior to accident

Engines

Pratt & Whitney R2800 CB17

Systems & Failure Modes

Ground Controlled Approach (GCA)

A radar-based landing system where a ground controller provides verbal instructions to the pilot to maintain the correct glidepath and centerline.

Runway Lighting

A system of approach, threshold, and runway edge lights; in this case, the red approach lights and initial runway pairs were non-functional, hindering visual transition.

Interesting Facts

01The aircraft was in full working order with all four engines running at the time of impact.
02The red runway approach lights and the first four pairs of runway lights were inoperative.
03The crew was not notified of the lighting deficiencies during their weather briefing in Anchorage.
04The GCA controller failed to use emergency frequencies or provide urgent corrections as the aircraft deviated below the glidepath.
05The flight was carrying 25,999 pounds of military cargo.
06Weather at the time included a 200-foot variable ceiling and 3/4 mile visibility in fog.
07GCA radio transmissions were not recorded, in direct violation of standing instructions.

Safety Actions & Advisories

GCA Standards Recommendation

The CAB recommended that the FAA Administrator take action to ensure personnel and equipment used in GCA approaches meet pertinent safety and operational standards.

Location

Shemya Air Force Base, Shemya, Alaska · 52.7122, 174.1136