What happened
On 7 December 2016, a Piper PA34-200T Senerva III, registration HB-LSD, was conducting a private, non-commercial night flight from Nuremberg to Basel-Mulhouse. The aircraft was on an ILS Z15 approach under Low Visibility Procedures (LVP) due to freezing fog and poor visibility.
As the aircraft approached runway 15, the pilot was notified of deteriorating visibility. While following the standard approach path, the aircraft began to deviate left of the runway centerline at approximately 1,300 meters from the threshold. The aircraft drifted toward the adjacent motorway, reaching a lateral deviation of about 260 meters.
At a height of only 30 feet above the motorway, the pilot realized the error and announced an intention to perform a missed approach. During the subsequent maneuver, the aircraft entered a continuous turn and executed a 360-degree right turn. Following a period of rapid vertical and horizontal flight path fluctuations, the aircraft likely stalled and struck the runway safety area, resulting in a post-impact fire. The pilot was fatally injured, and the aircraft was destroyed.
The investigation
The BEA examined radar data, air traffic control communications, and wreckage. Analysis of the engine speed via spectrum analysis showed that the pilot increased power for the go-around, with engine speed rising from 2,450 to 2,576 rpm. The wreckage showed the aircraft struck the ground with a nose-down pitch and wings level, with flaps fully extended.
Investigators also reviewed meteorological data, which confirmed the presence of freezing fog and moderate icing near the ground. Witness testimony from a motorist on the motorway corroborated the aircraft's steep descent and the pilot's attempt to initiate a go-around.
Findings
- The pilot deviated from the instrument approach path, likely due to using erroneous external visual references (mistaking the motorway for the runway) shortly before reaching the decision height.
- The pilot failed to immediately initiate a missed approach upon the initial deviation, likely because he believed he had established visual contact with the runway.
- The aircraft experienced significant flight path variations, suggesting the pilot suffered from spatial disorientation caused by the lack of external visual references in the fog.
- The aircraft likely stalled during the complex maneuvering of the missed approach, leading to the collision with the ground.