Investigation Summary
The accident occurred at the end of a flight from Chicago, conducted during the crew's circadian trough. The crew elected to land on Runway 14, which was shorter than the primary Runway 23, due to a misinterpretation of a NOTAM. The NOTAM stated 'NOT AUTH' for a portion of Runway 23 due to construction, leading the crew to believe the entire runway was closed. Although the ATIS later indicated Runway 23 was available, the crew remained anchored to their original plan for Runway 14. During the approach, the tower reported a tailwind component of 7 knots. The crew, already under high workload and fatigued, did not recalculate landing performance data. Upon touchdown, the aircraft drifted right of the centerline due to a crab angle and asymmetric thrust. Crucially, the number 1 thrust lever was moved forward of the idle position, which automatically stowed the speed brakes and disengaged the autobrake system. The crew did not notice these system changes immediately, and maximum manual braking was not applied until the aircraft was only 800 feet from the runway end.
Final Conclusions
The Transportation Safety Board of Canada (TSB) concluded in its final report (A18A0085, published 29 June 2021) that the overrun was caused by a combination of pilot fatigue, cognitive biases, and mechanical configuration errors during the landing roll. The crew's performance was degraded by insufficient restorative sleep and the timing of the flight. The inadvertent advancement of the No. 1 thrust lever after touchdown was the primary mechanical factor that prevented the aircraft from stopping within the available runway length. The TSB also noted that the terrain beyond the runway end safety area (RESA) contributed to the severity of the aircraft damage.
Video Analysis
Information Failure | Sky Lease Cargo Flight 4854 — A detailed look at the factors leading to the 2018 runway overrun in Halifax, including NOTAM misinterpretation and pilot fatigue.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Systems & Failure Modes
Autobrake System
Designed to provide automatic braking at a selected deceleration rate upon touchdown; it disengaged when the No. 1 thrust lever was moved forward.
Speed Brakes (Spoilers)
Aerodynamic surfaces on the wings that retract automatically if thrust levers are advanced, reducing drag and increasing lift, which is counterproductive during landing rollout.
NOTAM System
The presentation style of the Notice to Airmen was cited as ineffective, leading the crew to believe Runway 23 was closed.
Interesting Facts
- 01The aircraft was a Boeing 747-412F with 92,471 airframe hours and 16,948 cycles.
- 02The crew misinterpreted a NOTAM, believing the longer Runway 23 was entirely unavailable for landing.
- 03The No. 1 thrust lever was moved forward of idle for undetermined reasons after touchdown, disabling automatic deceleration systems.
- 04The aircraft crossed a 2.8-meter drop (embankment) located 166 meters past the end of the runway.
- 05All 3 crew members sustained minor injuries; the 1 passenger was uninjured.
Safety Actions & Advisories
Runway End Safety Area (RESA) Recommendation
The TSB reiterated Recommendation A07-06, urging Transport Canada to require all Code 4 runways to have a 300-meter RESA or an equivalent means of stopping aircraft.
Fatigue Management Watchlist
The TSB highlighted fatigue management as a key safety issue on its 2020 Watchlist following the investigation's findings on crew rest.
Location
ACCIDENT SITE · Coordinates taken from the official investigation report.