Incident Overview
On 26 October 2012 at 10:35 local time, a Tecnam P2006T twin-engine aircraft, registration S5-DTW, experienced a serious incident while approaching E. Rusjan Maribor Airport (LJMB). The flight originated from Krakow Airport (EPKK) under Visual Flight Rules (VFR) with a planned destination of Maribor. The aircraft was owned by Aviofun d.o.o. and operated by Express Airways d.o.o. There were one pilot and one passenger on board; both remained uninjured. The aircraft sustained partial damage that was repairable.
Flight Details
The pilot filed a flight plan and departed Krakow at 09:35 LT. After overflying the VFR waypoint DIMLO and entering Slovenian airspace, the pilot received information about increased cloud cover and reduced visibility at Maribor. Consequently, he decided to change the flight plan from VFR to Instrument Flight Rules (IFR) and continued the flight under IFR.
According to the pilot’s testimony, the flight proceeded without incident until establishing contact with the Instrument Landing System (ILS) and passing the MR waypoint. After crossing the Outer Marker (OM), the pilot reported difficulty maintaining the aircraft’s position during the instrument approach. Upon reaching the decision altitude, visual contact with the runway was not established, so the pilot initiated a missed approach procedure.
During the missed approach, the pilot stated that the aircraft’s speed increased and the variometer indicated a significant altitude loss. When the pilot glanced at the right artificial horizon, which showed a substantial difference in bank attitude, and simultaneously saw the proximity of terrain (a roof of a building and treetops), he abruptly pulled back on the controls to avoid a collision. The aircraft climbed and continued in visual low-level flight along familiar landmarks in the traffic pattern. The air traffic controller provided instructions and fired a flare to assist, but the pilot did not see it. The pilot then flew a visual circuit and landed safely on runway 32.
Weather Conditions
At the time of flight planning and departure, the destination airport had marginal meteorological conditions for visual flight, with a tendency to deteriorate. As the aircraft approached the Maribor Terminal Area (TMA), prevailing visibility and vertical visibility further decreased. METAR reports from the time indicate:
- 26/10/2012 09:30 UTC: Wind 02004KT, 3000m visibility, mist, scattered clouds at 300 ft, overcast at 600 ft, temperature 9°C, dew point 8°C.
- 26/10/2012 10:00 UTC: Wind 02005KT, 3500m visibility, mist, few clouds at 300 ft, overcast at 500 ft, temperature 9°C, dew point 7°C.
- 26/10/2012 10:30 UTC: Wind 36005KT, 4000m visibility, mist, overcast at 600 ft, temperature 9°C, dew point 7°C.
Vertical visibility during the ILS approach was characterized by 1/8 to 2/8 cloud cover with a base at 300 ft above the landing threshold elevation, and 3/8 to 4/8 cloud cover with a base at 500 to 600 ft.
Findings from Investigation
A few days after the incident, airport maintenance staff discovered fuel leaking from the aircraft’s wings and damage to the airframe during a routine hangar inspection. The owner and operator were notified, and the Slovenian Civil Aviation Authority’s Accident and Incident Investigation Service initiated an investigation.
Examination of the aircraft in the hangar revealed no anomalies in the functioning of either artificial horizon display. Further bench testing of these instruments was not conducted, and no complaints were raised during subsequent flights regarding their performance. Review of maintenance records related to the damage repair showed no irregularities in the indicators’ operation. The work orders for repairing the damage indicated that the Horizontal Situation Indicator (HSI) and the autopilot computer were replaced. According to the pilot, after overflying DIMLO, the autopilot disengaged several times automatically and was not used during the subsequent IFR and ILS phases.
Conclusion
The investigation did not determine a single probable cause for the incident. The report concluded with findings about the weather, pilot decision-making, and aircraft systems, but no explicit causal factor was assigned.