What happened
On a rainy afternoon at Ottawa/Mac anddonald Cartier International Airport, an Embraer EMB-145LR, registration N840HK, operated by Trans States Airlines LLC as United Express Flight 3363, veered off the runway during landing. The aircraft had arrived from Chicago O'Hare International Airport.
As the flight approached Runway 32, the crew encountered heavy rain and increasing winds. During the final stages of the approach, the aircraft was flying at speeds exceeding the company's stabilized approach limits. Just before touchdown, the captain applied maximum engine thrust, which caused the aircraft to float and touch down significantly further down the runway than recommended.
Upon landing, the aircraft experienced immediate hydroplaning due to a layer of water on the runway. The pilot applied maximum braking and subsequently engaged the emergency/parking brake, which caused the wheels to lock and prevented the anti-skid system from functioning effectively. The aircraft began to skid and yaw to the left, eventually exiting the left side of the runway. The incident resulted in no injuries to the 44 passengers and 3 crew members, though the landing gear collapsed, causing a fuel leak and damage to the wing.
The investigation
The investigation focused on the operational factors and environmental conditions present during the landing. Investigators examined the aircraft's approach speed, the configuration of the aircraft, and the state of the runway surface.
Key elements analyzed included:
- The aircraft's airspeed relative to the required approach speed (V APP).
- The impact of the heavy rain and the 4–6 mm water depth on the runway.
- The use of the emergency/parking brake during the landing roll.
- The condition of the tires, noting that three of the four main tires were underinflated.
- The lack of runway grooving on the landing surface, which increases hydroplaning risks.
Findings
Several contributing factors led to the runway excursion:
- Heavy rainfall created a contaminated runway surface, making the aircraft susceptible to dynamic hydroplaning.
- The flight crew maintained an approach speed that exceeded company-presulated limits and failed to initiate a go-around as required by standard operating procedures.
- The application of maximum thrust just before touchdown delayed the touchdown point and increased the landing distance required.
- The use of the emergency/parking brake during the rollout disabled the anti-skid system and prolonged the skid.
- Underinflated tires and a smooth landing technique further contributed to the loss of braking effectiveness.
Safety action
Following the incident, the Ottawa International Airport Authority initiated a multi-year rehabilitation program for its runways. This included the reconstruction of Runway 07/25 and plans for Runway 14/32, both of which were designed to include runway grooving to improve drainage and reduce hydroplaning risks. Additionally, Embraer updated its Aircraft Maintenance Manual to provide clearer descriptions regarding the brake system.