What aircraft was involved and where did it happen?

The accident on 2000-02-16 involved a Siai- Marchetti F 260, at nahe Schöntal, DE.

What was the probable cause of the accident?

The accident was caused by the pilot flying into cumulonimbus clouds containing turbulence and icing conditions, which led to an uncontrolled flight state.

Fatal VFR Flight into Cumulonimbus Clouds Near Schöntal

A private Siai-Marchetti F 260 crashed into a forest near Schöntal, Germany, resulting in two fatalities after flying into severe weather.

What happened

On February 16, 2000, a private Siai-Marchetti F 260 was conducting a visual flight rules (VFR) flight from Biberach to Aschaffenburg. The aircraft was occupied by the pilot in command and one passenger. Approximately 28 minutes after departure, the aircraft struck a heavily forested area near Schöntal with a significant longitudinal pitch. The impact resulted in two fatalities and the total destruction of the aircraft, as well as damage to the surrounding forest.

The investigation

Investigators examined the wreckage and determined that the landing gear was retracted at the time of impact. While the high degree of destruction prevented a full technical analysis, deformations on the propeller suggested the engine was producing power at the moment of impact. Radar data from Deutsche Flugsicherung GmbH showed that for the final eight minutes of flight, the aircraft maintained a steady northwest course at flight level 25 (approximately 2,500 ft MSL) without any significant deviations in course or altitude before disappearing from radar.

The pilot held a private pilot license with an instrument rating and had a total of 1,033 flight hours, though only 32 of those were in this specific aircraft type. Notably, the pilot's last flight prior to the accident had occurred several months earlier, in August 1999.

A meteorological assessment by the German Meteorological Service (DWD) revealed that the flight path was positioned behind a departing cold front, bringing unstable maritime air. The area was experiencing heavy snow, sleet, or graupel showers, with intermittent thunderstorms. The aircraft was flying within cumulonimbus clouds that presented conditions of moderate turbulence and moderate icing. The aircraft was not equipped with any anti-icing or de-icing systems.

Findings

The aircraft entered cumulonimbus clouds while operating under VFR.
The presence of moderate icing in the clouds could have rapidly degraded the aircraft's performance, potentially leading to an aerodynamic stall.
Moderate turbulence within the clouds was sufficient to induce spatial disorientation in a pilot, particularly one who had not flown the aircraft type recently.
The pilot failed to exit the uncontrolled flight condition in a timely manner.