Occurrence
Sky Lease Cargo flight 4854 (KYE4854), a Boeing 747-412F aircraft (U.S. registration N908AR, serial number 28026), was operating from Chicago/O’Hare International Airport, Illinois, United States, to Halifax/Stanfield International Airport, Nova Scotia. The aircraft carried 3 crew members, 1 passenger, and no cargo.
The crew conducted an instrument landing system approach to Runway 14. When the aircraft was 1 minute and 21 seconds from the runway threshold, the crew realized there was a tailwind but did not recalculate landing performance data, likely due to limited time. The unexpected tailwind increased the landing distance required, though this distance did not exceed the runway length.
The aircraft touched down firmly at approximately 0506 Atlantic Standard Time, during darkness. After touchdown, for undetermined reasons, the No. 1 engine thrust lever was moved forward of idle, causing the speed brakes to retract and the autobrake system to disengage, increasing the stopping distance. A right crab angle of 4.5° on initial touchdown, combined with crosswind and asymmetric reverser selection, caused the aircraft to deviate right of the runway centerline.
During the landing roll, the pilot monitoring focused on the lateral drift and did not make required callouts regarding deceleration device positions. Manual braking began 8 seconds after touchdown, but maximum braking effort did not occur until 15 seconds later, when the aircraft was 800 feet from the runway end. At that point, stopping on the runway was impossible. Five seconds later, the aircraft departed the runway end at 77 knots and came to a stop 270 meters (885 feet) beyond.
Findings
The aircraft struck approach light stanchions and the localizer antenna array. The No. 2 engine detached from its pylon during the impact and came to rest under the left horizontal stabilizer, causing a fire in the tail section. The emergency locator transmitter activated. Aircraft rescue and firefighting personnel responded. All three crew members sustained minor injuries and were taken to the hospital; the passenger was not injured.
The overrun involved crossing a significant drop of 2.8 meters (9 feet) approximately 166 meters (544 feet) past the runway end. This terrain exceeded the 150-meter (492 feet) runway end safety area proposed by Transport Canada but was within the International Civil Aviation Organization recommended 300-meter (984 feet) area. In 2007, the Transportation Safety Board of Canada recommended (TSB Recommendation A07-06) that Transport Canada require all Code 4 runways to have a 300-meter runway end safety area or equivalent means of stopping aircraft.
The investigation included a fatigue analysis that identified two fatigue risk factors: the timing of the flight and insufficient restorative sleep in the 24-hour period before the occurrence. Fatigue management is one of the issues on the TSB’s Watchlist 2020, along with runway overruns.
Aftermath
The aircraft was damaged beyond repair. The occurrence highlights ongoing safety issues related to runway end safety areas and fatigue management.