What happened
On March 3, 1997, an Embraer 120 operated by Pantanal Linhas Aéreas, registration PT-MFC, was performing a scheduled flight from Campo Grande to Vilhena, Brazil. Upon approaching the destination, the crew was notified that the airport was closed for instrument operations because the ceiling was 100 feet below the required minimum.
Despite this information, the crew decided to proceed with the ECHO 01 NDB procedure for runway 03, intending to divert to Cuiabá if visual conditions were not met. During the approach, the pilot flying—a student pilot undergoing command training—selected an altitude of 2,500 feet on the altitude selector, which was below the required Minimum Descent Altitude (MDA) of 2,560 feet.
The aircraft continued to descend and struck trees near a farm approximately 3 km from the runway threshold. The impact caused the aircraft to strike the ground and slide for 160 meters, at which point a fire broke out in the left engine and spread throughout the airframe. The aircraft was destroyed by the fire. Of the 13 people on board, six individuals sustained minor injuries (three crew members and three passengers), while ten passengers were uninjured.
The investigation
CENIPA's investigation focused on the crew's decision-making and cockpit management. Investigators found that the instructor pilot, seated in the right seat, failed to properly supervise the student pilot. Instead of monitoring internal flight parameters, the instructor was looking outside the cockpit attempting to locate the runway via ground lights. However, a blackout in the city of Vilhena meant the expected visual references were unavailable.
Technical analysis revealed that the aircraft's autopilot failed to capture the selected 2,500-foot altitude, leading to the uncontrolled descent. Furthermore, the investigation noted that the aircraft was operating without a Cockpit Voice Recorder (CVR), which had been removed for maintenance, violating the Master Minimum Equipment List (MMEL) requirements. The Flight Data Recorder (FDR) was also unreadable due to fire damage and corrosion.
Findings
- Flight Indiscipline: The crew intentionally violated regulatory standards (RBHA 121) by executing an instrument approach while weather conditions were below the published minimums.
- Deficient Crew Coordination: There was a lack of standard "call outs" during critical phases of the descent, and the instructor failed to perform cross-checks of altitude and vertical speed.
- Fixation of Attention: The student pilot focused excessively on monitoring the artificial horizon as instructed, neglecting other vital instruments like the altimeter.
- Poor Judgment and Complacency: The instructor demonstrated overconfidence in the student's ability and failed to intervene when the incorrect altitude was selected.
- Environmental Factors: A local power outage prevented the crew from using city lights as a spatial reference, contributing to disorientation.
- Improper Maintenance Oversight: The aircraft was operating without a CVR in violation of the MMEL.