Canadian investigators probing the 17 February crash of an Endeavor Air MHIRJ CRJ900 while landing in windy conditions at Toronto Pearson airport are focussing on the descent rate of the regional jet.
The Transportation Safety Board of Canada (TSB) is also examining the actions of the pilots and Endeavor’s pilot training.
In a preliminary accident report released on 20 March, the agency says the CRJ900 had been descending at 1,098ft/min the instant before it hit runway 23 with 3g of vertical acceleration.
The landing caused the jet’s right-side main landing gear to fail, with the TSB noting that the gear’s shock struts “are designed to absorb energy” of a 720ft/min descent when the aircraft is at its maximum landing weight.
“During touchdown… the side-stay attached to the aircraft’s right main landing gear fractured, the landing gear retracted and the wing root fractured between the landing gear and the fuselage,” says TSB lead investigator Ken Webster.
“The right wing detached from the fuselage, releasing a cloud of jet fuel, which caught fire while the aircraft began to slide along the runway.”
The CRJ900 (N932XJ) was operating as flight 4819 from Minneapolis-Saint Paul International airport to Toronto Pearson airport on 17 February. Delta Air Lines owns Endeavor Air, which flies regional routes on its parent’s behalf.
“We remain fully engaged as participants in the investigation led by the Transportation Safety Board of Canada. Out of respect for the integrity of this work that will continue through their final report, Endeavor Air and Delta will refrain from comment,” the carriers say.
At the time of the landing, winds at Toronto were blowing from 270° at between 20kt (37km/h) and 28kt, while gusting to about 35kt, in blowing snow, the TSB says.
At about 175ft altitude, the jet was descending at 672ft/min and flying at 144kt indicated airspeed. Moments later, its airspeed jumped to 154kt, prompting the first officer, who was flying the approach, to pull back the thrust levers, decreasing engine speed from 64% to 43%.
From then until touchdown, the jet continued slowing and its descent rate increased. It touched down at 14:12 local time while flying at 134kt and descending at 1,098ft/min, while banked 7.5° right and pitched 1° nose-up.
After its right main gear failed and its right wing detached, the jet slid along the runway and rolled right onto its back, then slid over a section of snow-covered grass and onto runway 15L, where it stopped, inverted.
“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,” says the TSB. “Some passengers had difficulty releasing the buckles on their safety belts due to being inverted. Some of the injuries sustained by the passengers occurred when they unbuckled their safety belts and fell to the ceiling.”
All 80 people aboard the jet – two pilots, two flight attendants and 76 passengers – evacuated. The incident left 21 people injured, including two with serious injuries, the TSB says.
The jet’s captain had worked for Endeavor Air since October 2007 and had logged 3,570h of flight time, including 764h in the CRJ900, while the first officer was a new hire, having joined the airline in January, and had logged 1,422h of flight time, including 419h in CRJ900s.
Webster says the TSB has found “no obvious pre-existing malfunctions” with the CRJ900.
As the investigation continues, the TSB will specifically focus on the wing structure’s metallurgy and certification of the jet’s landing gear and wing structure. It will also examine “landing techniques, hard landings and pilot training”, and “organisational and management factors”, Webster says.
