Delta plane that crashed at Pearson airport was travelling at high rate of descent, prelim report suggests
Too early to determine what caused crash, safety board says in statement
A warning system on the Delta Air Lines flight that crashed at Pearson airport last month sent an alert indicating a high rate of descent less than three seconds before the plane touched down, according to a preliminary report.
Less than a second before touchdown, the plane's rate of descent was 1,110 feet per minute. The flight manual defines a hard landing as a "landing at a vertical descent rate greater than 600 ft/min when the aircraft's gross weight is less than or equal to [maximum landing weight]," the report says.
The Delta Air Lines flight weighed less than its maximum allowable take-off weight at the time of the crash.
The report also says that less than a second before landing, the angle of the plane's aircraft, known as the pitch attitude, was one degree. The flight operations manual states pitch attitude at touchdown should be between three and eight degrees, the report said.
The report, released Thursday, is part of an ongoing investigation by the Transportation Safety Board of Canada into the Feb. 17 crash, which sent 21 people to hospital.
"It is too early to draw conclusions as to the causes of this accident," the board said in a news release Thursday. "A full investigation report, which will include the TSB's analysis into why the accident happened and the Board's findings, will be released in due course."
The flight, operated by Delta Air Lines subsidiary Endeavour Air, took off from Minneapolis with 76 passengers, two flight crew members and two cabin crew members. The aircraft was a CL-600-2D24 (Regional Jet Series 900) manufactured by Bombardier Inc. in 2008.
Prior to the crash, the flight "proceeded uneventfully," the report said.
The first officer was the pilot flying the plane. At the time of the crash, she had around 1,422 hours total flight time, including 418.7 hours on the type of aircraft involved in the incident, the report said.
The captain was the pilot monitoring for the flight. He had 3,570 hours total flight time at the time of the crash, including 764 hours on the same aircraft type.
Right landing gear fractured after touchdown, report says
At 2 p.m., winds were gusting to 35 knots in the area, the report said. After flight crew received clearance to land at Runway 23 at Pearson airport, they flew the approach at 149 knots, "given the reported wind gusts," it said.
Around 2.6 seconds before touchdown, a "sink rate" alert sounded, "indicating a high rate of descent," the report said. The alert came from the plane's enhanced ground proximity warning system.
At the time the alert sounded, the plane's airspeed was 136 knots, the report said.
Less than a second before touchdown, the aircraft's indicated airspeed was 134 knots and its ground speed was 111 knots. Around 2:12 p.m., the right main landing gear touched the runway.
"At touchdown, the following occurred: the side-stay that is attached to the right [main landing gear] fractured, the landing gear folded into the retracted position, the wing root fractured between the fuselage and the landing gear, and the wing detached from the fuselage, releasing a cloud of jet fuel, which caught fire," the report said.
"The exact sequence of these events is still to be determined by further examination of the fracture surfaces."
The plane then began to slide along the runway, eventually going off the right side into a snow-covered grass area and coming to rest on Runway 15L, near the intersection with Runway 23.
Meanwhile, the right wing became fully detached from the plane and slid around 215 feet further along Runway 23.
Once the aircraft came to a stop, an evacuation began. There were 21 people injured among the 80 on board, with two people reported to have serious injuries.
"Passengers were hanging upside down in their seats, suspended by their safety belts, and many of the carry-on baggage and other items ended up on the aircraft ceiling," the report said.
Some of the injuries happened when passengers unbuckled their belts and fell, the report said.
Aircraft rescue and fire-fighting (ARFF) crews arrived on scene around five minutes after the crash landing, the report said. The crews entered the fuselage after the plane was evacuated.
"Shortly thereafter, an explosion occurred outside the aircraft in the area of the left wing root," the report reads. "The cause of this explosion has yet to be determined."
The report concluded with a list of the current areas the board is focusing on for its investigation, including an examination of the landing gear and wings, landing techniques and pilot training, and flight deck door structure and design.
Plane had a hard, flat landing, expert says
John Gradek, an operations and integrated aviation management professor at McGill University, said the plane's descent rate was "significantly higher than you would expect to have in a given landing area."
"It was, by all classifications, a hard landing," he said.
The nose only being up one degree is also not typical, and can result in a flat landing that puts stress on the aircraft, he said.
Gradek said he is interested to hear more about the conversations in the cockpit between the captain and first officer in the lead up to touchdown — which he said should include discussions about descent rate, speed and nose attitude.
"That's going to be a crucial piece of evidence that the TSB will be researching in the next few months as they prepare their final report," he said.
Series of legal cases filed by passengers
All passengers who were hospitalized were released within days of the crash. But new U.S. court filings by a Minneapolis law firm say that nine Canadians who were in the crash continue to suffer from "extreme bodily and mental injuries," as well as economic losses.
The flight crew "failed to observe the most fundamental procedures for a landing approach into [Pearson], failed to appropriately monitor flight conditions on approach, and failed [to] communicate and react in the cockpit to those flight conditions," lawyers Bryan L. Bleichner and Christopher P. Renz wrote in the filings, reviewed by CBC News.
These filings are the latest in a series of cases filed in connection with the flight. Toronto law firm Rochon Genova announced the day after the crash that it had been retained by certain passengers and their families.
The preliminary report indicates "the first officer that was flying the aircraft essentially had a very hard landing … [and] drove the plane into the runway," said aviation lawyer Andres Pereira.
Pereira represents Marthinus Lourens, a passenger on the flight who is suing Delta Air Lines and Endeavor Air. Lourens suffered a fractured right knee and several herniated discs after the crash, he said.
The report shows the plane was descending at a "fairly unusual" high rate of speed, considering its distance from the runway, Pereira said.
He said Delta Air Lines and Endeavour Air Lines are responsible for how they trained the first officer. As well, he said information in the report indicates the captain "seemed to be a training pilot that did more work in front of a simulator than he did actually flying on a regular basis."
According to the report, the captain is employed as a flight crew member and a simulator instructor. At the time of the crash, he had flown 3.5 hours in the previous 30 days.
"Whoever scheduled these two individuals to fly together, it seems to me, has some questions to answer," Pereira said.
Ken Webster, the TSB's lead investigator for the incident, told CBC News the flight crew were both qualified for the flight.
"There's nothing indicating the flight crew was not experienced," he said. "Looking into their backgrounds is something more we'll do to figure out why that accident happened."
In a statement Thursday, a spokesperson for Delta Air Lines and Endeavour Air said they would not comment on the preliminary report "out of respect for the integrity of this work that will continue through their final report."
Passenger says report confirms his experience on plane
Clayton Bouffard, who lives near Sudbury, Ont., was a passenger on the plane, along with his wife. He said the report confirmed his experience on the flight — that the plane descended too fast and it was "not a normal landing."
"The whole descent seemed to be off… I remember telling my wife that we seemed to be going fast," he said.
The plane was leaning to the right before it touched down, Bouffard said.
"We definitely hit hard," he said.
After the plane came to a stop, his wife helped him take off his seatbelt as he was unable to do. He said he continues to have a sore neck and hasn't slept well since the crash.
"I'm just thankful all 80 people survived that," he said. "It's amazing we all survived."
ABOUT THE AUTHOR
With files from The Canadian Press, Thomas Daigle and Michelle Song