Investigation Summary
Flight 315 was a transatlantic charter flight arranged through the Canadian Legion for passengers visiting family in the United Kingdom. After refueling stops in Reykjavík and Goose Bay, the crew elected to overfly Goose Bay and proceed directly toward Montreal. While cruising at 6,000 feet in the vicinity of Quebec City, the aircraft entered a cumulonimbus cloud formation. The resulting severe turbulence caused a total loss of control, sending the DC-4 into a spin and a 70-degree nose-down dive. The aircraft struck the ground at approximately 200 knots, creating a large crater in a swampy, wooded area. The impact was so severe that the aircraft disintegrated, and the recovery of remains was difficult, leading to mass burials and later memorials in Toronto and Issoudun.
Final Conclusions
The accident was attributed to severe turbulence encountered while flying in a cumulonimbus cloud. This led to a chain of events resulting in a complete loss of control and a near-vertical dive to the ground. The investigation highlighted the dangers of flying through thunderstorm cells without weather radar, which was not standard on all transport aircraft at the time.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
First Officer
Navigator
Systems & Failure Modes
Airframe
The Douglas DC-4 suffered a total loss of control and structural disintegration upon high-speed impact.
Meteorological Navigation
The crew flew into a severe cumulonimbus cell, encountering turbulence that exceeded the aircraft's controllable limits.
Interesting Facts
- 01The crash was the deadliest aviation accident in Canadian history until the 1963 crash of Trans-Canada Air Lines Flight 831.
- 02The aircraft struck the ground in a 70-degree nose-down attitude at a speed of 200 knots.
- 03Twelve of the victims were from Hamilton, Ontario, including the grandmother of future Deputy Prime Minister Sheila Copps.
- 04The flight was a charter for the Imperial Division of the Canadian Legion.
- 05The aircraft was a Douglas DC-4 (C-54 Skymaster) built in 1944.
Safety Actions & Advisories
Memorialization
A granite memorial was commissioned by the federal government in the late 1990s in a cemetery near the crash site to ensure the victims were not forgotten.
Weather Radar Recommendations
The investigation highlighted the critical need for airborne weather radar on transport aircraft to detect and avoid severe cumulonimbus cells, a technology that was not yet standard at the time of the accident.