What happened
On November 15, 2011, an Embraer 145, registration PR-PSK, operated by Passaredo Linhas Aéreas, was performing a night approach to Uberlândia Airport (SBUL) under instrument flight rules. The flight had originated from Guarulhos (SBGR). Due to low visibility, the crew initially attempted a VOR approach to runway 04 but executed a missed approach. They subsequently transitioned to an NDB approach for runway 22.
During the final approach, the aircraft maintained an excessive speed and a high glide path. The aircraft crossed the threshold at 100 feet with an indicated airspeed of 138 knots, which was 15 knots above the reference speed. The aircraft touched down on the right side of the runway between the 1,500-foot and 2,000-foot markers at 134 knots. Upon touchdown, the crew noticed the aircraft was sliding and failing to decelerate effectively due to simultaneous viscous and dynamic hydroplaning caused by the wet runway. Realizing the aircraft would not stop within the remaining runway distance, the crew steered the aircraft off the left side of the runway onto the grass, where it traveled approximately 120 meters before coming to a complete stop. There were no fatalities among the 3 crew members and 27 passengers, though the aircraft sustained light damage to the landing gear.
The investigation
CENIPA's investigation focused on the environmental conditions, the aircraft's performance, and the crew's decision-making. The investigation examined the impact of the wet runway and the lack of visual approach aids at the time of the incident. Investigators analyzed the flight parameters, noting that the aircraft was significantly above the planned approach speed and glide slope. The investigation also reviewed the lack of coordination during the rapid transition between the missed approach and the second approach attempt.
Findings
- Hydroplaning: The runway was contaminated with water, leading to both dynamic and viscous hydroplaning.
- Approach Profile: The crew failed to make effective corrections to reduce approach speed and stabilize the glide path, resulting in an approach 12 knots faster than planned.
- Decision Making: The crew's decision to proceed with the runway 22 approach was made quickly following a missed approach, leaving little time to study the runway conditions or prepare for the new approach.
- Infrastructure: The absence of a Visual Approach Slope Indicator (PAPI) at runway 22 made it difficult to maintain an adequate glide path during the night approach in rainy conditions.
- Crew Coordination: There was a lack of monitoring/alerting between the crew members regarding the excessive speed and altitude during the final approach.
Safety action
CENIPA issued several safety recommendations, including:
- A recommendation to ANAC to facilitate the installation of a PAPI system at Uberlândia Airport.
- A recommendation to ANAC to ensure all Brazilian airports operating turbo-jet aircraft have appropriate visual approach aids.
- A recommendation to DECEA to establish unified criteria for the implementation of visual approach slope indicators.
- A recommendation for the development of scientific methodologies to evaluate runway water contamination levels at public airports.