What happened
On December 13, 1999, a flight instructor operating a Cessna 172 R intended to perform a long-distance VFR cross-country flight from Jena-Schöngleina to Saarbrücken. The flight was meant to build the necessary experience for a future commercial pilot license.
After departing from an airfield at 1,247 ft MSL, the pilot initially climbed to 3,000 ft. While flying near Rudolstadt, the pilot noted increasing cloud cover and attempted to climb above the clouds to maintain visual contact with the ground. However, as the aircraft passed the freezing level, it began to encounter icing while flying through individual clouds.
Unable to reach the cloud tops, the pilot initiated a descent to find better conditions, which resulted in entering Instrument Meteorological Conditions (IMC). During a descent through a snow shower over the mountainous Thuring and Forest terrain, the aircraft struck treetops. A second impact occurred approximately one to two minutes later near the village of Frauenwald. The aircraft subsequently struck the forest floor, resulting in the destruction of the aircraft and damage to the forest. The pilot sustained minor injuries to the back of the head.
The investigation
The BFU investigation examined the aircraft's condition and the meteorological environment. The investigation found that the engine was at idle upon impact and the propeller showed minimal damage. The landing flaps were extended to 10 degrees. There were no reported technical defects, and sufficient fuel remained on board.
Meteorological analysis revealed that while the weather forecasts (METAR/TAF) indicated good visibility at major airports, the local conditions in the Thuringian Forest were characterized by unstable maritime air, wind gusts, and snow showers. Crucially, while the pilot believed the cloud tops were reachable, data from a nearby weather station indicated the cloud ceiling was at FL 240, making it far too high for a VFR flight in a Cessna 172 R.
Findings
- The pilot attempted to climb above a cloud layer that was significantly higher than the aircraft's service ceiling.
- The decision to descend to avoid icing led the pilot into IMC, where visual reference to the terrain was lost during a snow shower.
- The pilot's attempt to maintain VFR flight under deteriorating weather conditions created an inescapable situation.
- The aircraft struck trees due to the lack of visual ground reference and the pilot's spontaneous decision to attempt an emergency landing in the wooded area after the first tree strike.