What happened
During an approach in instrument meteorological conditions, the aircraft encountered freezing rain, mist, and ice pellets. As the flight progressed through the descent, the aircraft type began accumulating moderate clear ice. During this phase, a master warning light alerted the crew to a failure in the horizontal stabilizer heat system. While the crew followed the abnormal procedures checklist by configuring the aircraft at 120 knots with 10 degrees of flaps, the backup deicing system for the horizontal stabilizer was not engaged.
The aircraft landed on a 7,753-foot runway that was covered in slush. The touchdown occurred 1,500 feet down the runway. Due to the surface conditions, the aircraft experienced a lack of braking action and antiskid functionality for the first 3,000 feet of the roll. This left only 3,253 feet of runway available for deceleration, which was insufficient compared to the 3,445 feet required for a dry runway.
Upon identifying a downhill embankment and support poles at the end of the runway, the captain steered the aircraft off the right side of the runway to avoid a collision with the poles. As the aircraft descended the embankment, the nose landing gear collapsed, leading to the end of the sequence.
Findings
Investigation into the event highlighted that the failure to activate the horizontal stabilizer deice backup system was a critical factor during the accumulation of ice. Additionally, the combination of a contaminated runway surface and the lack of effective braking or antiskid performance contributed to the inability to stop within the remaining runway length.