Background
A cargo flight operating on behalf of DHL departed Managua, Nicaragua, destined for Saltillo, Mexico, with an intermediate stop in Tapachula, Mexico. The aircraft carried two passengers and two pilots.
Flight Sequence
During a night approach to Saltillo Airport, the crew was cleared to land on runway 17. One minute later, the crew initiated a go-around and decided to divert to Monterrey Airport, which had been designated as the alternate. However, due to poor flight preparation, the crew was unaware that Monterrey Airport was closed to traffic that night. Consequently, the crew returned to Saltillo and was again cleared to land on runway 17. At that time, weather conditions were marginal with limited visibility due to fog.
The crew conducted an ILS CAT I approach. The pilot-in-command descended below the minimum descent altitude (MDA) and continued the approach despite not establishing any visual contact with the runway and its equipment. The aircraft landed hard to the right of the runway and on the last third of the runway. After landing, the aircraft rolled for a few dozen metres, lost its nose gear, and came to rest against an embankment. All four occupants were injured, and the aircraft was damaged beyond repair.
Investigation Findings
The official investigation identified the probable cause as continuing the precision approach (ILS CAT 1) in conditions of reduced visibility due to fog, with no visual contact with the runway at an airport below minimums. This resulted in an abrupt landing misaligned to the right on the last third of the runway during a second landing attempt. The continuation of the landing was attributed to the lack of fuel to fly to a second alternate airport not contemplated in the operation.
Contributing factors included: 1. Lack of analysis of pre-flight operational information, including current NOTAMs, METAR, forecasts, fuel to a second alternate airport, and flight tracking. 2. Unstabilized approach. 3. Lack of application of CRM concepts. 4. Lack of adherence to procedure for providing METAR and NOTAM to the crew for dispatch. 5. Lack of adherence to procedure for flight control and tracking. 6. Lack of procedures to establish two alternate airports when the destination airport is below minimums. 7. Lack of company supervision, operation, and maintenance surveillance of aircraft flight recorders.
Probable Cause
The probable cause, as stated by the official investigation, was continuing the precision approach (ILS CAT 1) in conditions of reduced visibility by fog (no visual contact with the runway at an airport below minimums), which resulted in an abrupt landing misaligned to the right on the last third of the runway during a second landing attempt. The continuation of the landing was due to the lack of fuel to fly to a second alternate airport not contemplated in the operation.