Introduction
On 13 October 2015, a Bombardier DHC-8-402, registration OE-LGL, operated by an airline, was involved in a serious incident approximately 3 km southwest of Lugano Airport (LSZA), Switzerland. The event consisted of a dangerous proximity to terrain during a defined visual approach in marginal weather conditions.
Event Sequence
According to the investigation, the flight was conducting a visual approach to Lugano. The weather at the time was marginal, with reduced visibility and low clouds. The crew initiated the approach but did not abort in time to avoid getting dangerously close to terrain. The aircraft's enhanced ground proximity warning system (EGPWS) likely activated, although the exact details are not specified in the available source. The crew ultimately landed safely, and no injuries or aircraft damage were reported.
Findings
The investigation identified several causal factors:
- The flight operations company developed and trained an unsuitable visual approach procedure.
- There was inadequate cooperation among supervisory authorities regarding the visual approach procedure.
- The crew aborted the visual approach too late.
Additionally, a contributing factor was a lack of information exchange between the airport authority and the Swiss Federal Office of Civil Aviation (BAZL).
Causes
The serious incident was attributed to a dangerous terrain proximity during a defined visual approach in marginal weather, resulting from a combination of the following causal factors:
- Development and training of an unsuitable visual approach procedure by the flight operations company.
- Inadequate cooperation of the supervisory authorities regarding the visual approach procedure.
- Too late abort of the visual approach.
A contributing factor was the lack of information exchange between the airport authority and the BAZL.