Airport (less than 10 km from airport)

The accident is attributable to the fact that on the final approach, in own navigation, of the standard VOR/DME approach 28 the aircraft flew controlled into a wooded range of hills (controlled flight into terrain – CFIT), because the flight crew deliberately continued the descent under instrument flight conditions below the minimum altitude for the approach without having the necessary prerequisites. The flight crew initiated the go around too late.
The investigation has determined the following causal factors in relation to the accident:
• The commander deliberately descended below the minimum descent altitude (MDA) of the standard VOR/DME approach 28 without having the required visual contact to the approach lights or the runway.
• The copilot made no attempt to prevent the continuation of the flight below the minimum descent altitude.
The following factors contributed to the accident:
• In the approach sector of runway 28 at Zurich airport there was no system available which triggers an alarm if a minimum safe altitude is violated (minimum safe altitude warning – MSAW).
• Over a long period of time, the responsible persons of the airline did not make correct assessments of the commander’s flying performance. Where weaknesses were perceptible, they did not take appropriate measures.
• The commander’s ability to concentrate and take appropriate decisions as well as his ability to analyse complex processes were adversely affected by fatigue.
• Task-sharing between the flight crew during the approach was not appropriate and did not correspond to the required procedures by the airline.
• The range of hills which the aircraft came into contact with was not marked on the approach chart used by the flight crew.
• The means of determining the meteorological visibility at the airport was not representative for the approach sector runway 28, because it did not correspond to the actual visibility.
• The valid visual minimums at the time of the accident were inappropriate for a decision to use the standard VOR/DME approach 28.

It was determined that the aircraft struck the ground in a gear and flaps up configuration and that both engines were rotating at the time of impact. The left engine nevertheless provided less power than the right at the very moment of their respective impact. The right engine power lever was in sector beta before impact and no anomalies were reported by the crew before the accident. In conclusion, it is believed that the accident was probably due to a loss of control during an engine failure exercise, without however being able to determine with exactitude the chronology of the actions carried out by the crew.

The accident was the consequence of an incorrect assessment of the situation by the commander of the aircraft during the approach, which resulted in errors in the piloting techniques, expressed in:
- Transition from intense icing conditions to active descent with a transition from the originally planned instrument approach to a visual approach;
- Failure to take into account the possibility of complex meteorological conditions in preparation for the approach and during the approach - the crew did not consider the possibility of going around or returning to the point of departure;
- Maintaining an unjustified low airspeed and high vertical descent speed during an approach with poor altitude control;
Associated factors were:
- Difficult weather conditions due to severe icing conditions;
- Reassessment by the aircraft commander of his knowledge and experience in controlling the An-28 aircraft in adverse weather conditions;
- Failure to comply with the requirements of the Airplane Flight Manual of the An-28 aircraft for the operation of aircraft systems and crew resource management;
- Failure to comply with the Airplane Flight Manual in terms of timely termination of the approach and transition to climb;
- The copilot, taking into account the large flying experience of the aircraft commander and overestimating his flight and navigation skills, behaved passively and did not provide him with adequate assistance in difficult conditions during the approach;
- Transition from an instrument approach to a visual approach without ATC clearance;
- The lack of 32 visual assessment of the angle of the descent trajectory (PAPI system) on the runway.

No technical anomalies were found on both engines. The fuel selector was positioned on the auxiliary tanks who had sufficient fuel at the time of the accident. It was reported that the pilot elected to continue the approach on one engine, letting himself be carried away by the luck factor that he benefited in the past in other similar situations.

The (undetermined) pilot-at-the-controls' early, and over rotation of the airplane's nose during the takeoff attempt, and his failure to maintain directional control. Also causal, was the captain's inadequate remedial action, both during the takeoff attempt and after the airplane departed the runway.

The pilot's failure to remove the control gust lock prior to takeoff and his failure to abort the takeoff with sufficient runway remaining to stop the airplane on the runway.

The accident resulted due to a loss of control (aircraft becoming uncontrollable in the pitch and roll axis), which occurred approximately 35 to 40 seconds after lift-off/rotation. It was induced and aggravated by a 16% overload condition as well as the exceedance of the certified aft CG limitation of the aircraft. The investigation revealed that the aircraft was overloaded by approximately 16% 699.6kg). The cargo was not secured, nor was there a seat or a restraining device in the aircraft for the passenger that was onboard the ill-fated flight. The last Mandatory Periodic Inspection prior to the accident was certified on 30 May 2001 at 4 353.1 airframe hours, by AMO No. 273. Since the inspection was certified a further 96.6 hours were flown. The Certificate of Airworthiness for the aircraft was invalid at the time of the accident, as both engines have exceeded their TBO (time between overhaul) by approximately 185 hours.

The inadequate planning/decision and the exceeded crosswind component by the pilot. The gusts were a contributing factor.