The Delta Air Lines flight that overturned at Pearson International Airport last month had a steep descent before crashing, according to a preliminary report.
Less than a second before touchdown, the aircraft was descending at a rate of 1,110 feet per minute, which is classified as a “hard landing.”
According to the flight manual, a hard landing occurs when the vertical descent rate exceeds 600 feet per minute while the aircraft’s weight is at or below its maximum takeoff weight.
At the time of impact, the plane was under its maximum landing weight.
The preliminary report also noted that the aircraft’s pitch attitude was just one degree seconds before the crash. Under normal conditions, it should be between three and eight degrees.
The investigation into the crash is still ongoing.
In a news release, the board stated that “it’s still too early to draw conclusions about the cause of the incident.” They added that a full report, including the TSB’s analysis, will be released once it becomes available.
How It Unfolded
The aircraft departed from Minneapolis with 76 passengers, two cabin crew members, and two flight crew members on board. It was a CL-600-2D24, manufactured by Bombardier Inc. in 2008 and operated by a Delta Air Lines subsidiary.
Everything appeared normal before the crash.
According to the report, the first officer was piloting the aircraft at the time of impact. She had over 1,400 hours of total flight experience, including nearly 420 hours on the Regional Jet Series 900—the same model involved in the crash.
The captain, who had nearly 3,600 hours of total flight time, was serving as the monitoring pilot for the flight.
Once the flight crew received clearance to land at Pearson Airport, they approached the runway at 149 knots. About three seconds before touchdown, the aircraft’s ground proximity warning system issued an alert, warning that the plane was “descending at a high rate.”
At the time of the alert, the aircraft’s airspeed was 136 knots.
Less than a second before landing, the indicated airspeed had dropped to 134 knots. At approximately 2:12 p.m., the right landing gear made contact with the runway, with the plane’s ground speed recorded at 111 knots.
Moments later, part of the main landing gear fractured, causing the wing to detach from the aircraft. This released jet fuel, which then ignited.
According to the report, “the exact sequence of these events” is still under investigation.
The aircraft skidded down the runway before eventually coming to a stop on Runway 15L upside down. The right wing had completely separated from the fuselage and was found over 200 feet away on Runway 23.
Once the plane came to a stop, passengers and crew began evacuating. Of the 80 people on board, 21 were injured, including two who sustained serious injuries.
According to the report, passengers were left hanging upside down, suspended by their seat belts, while carry-on luggage and other items were scattered across the cabin’s ceiling. Many passengers were injured when they unbuckled their seat belts and fell to the floor.
Those who were hospitalized were released within days of the incident.
Aviation management professor John Gradek stated that the cockpit conversation between the first officer and captain about the plane’s speed, nose attitude, and descent rate will be a “crucial piece of evidence” in the ongoing investigation.
