History of the Flight
On Monday 28 August 2023, the owner of Christen Eagle II LN-TBN planned a flight with a passenger from Reinsvoll airfield in Innlandet county. They intended to fly sightseeing over Toten followed by aerobatics over the airfield. The aircraft took off at 1817 hrs local time. After approximately 30 minutes of flight, they returned to Reinsvoll and performed basic aerobatic manoeuvres. Following the last manoeuvre, they continued south for 2–3 km before turning back toward the airfield. Witnesses reported hearing the engine sputter for two to three seconds, after which it ran normally again. While approaching from the south-west, the aircraft's nose suddenly pitched down. Three witnesses described hearing a bang just before the pitch-down. The aircraft crashed in forested terrain approximately 550 metres south of the threshold of runway 34 at Reinsvoll airfield. Both the pilot and passenger died.
Injuries and Damage
The pilot and passenger sustained fatal injuries. The aircraft was destroyed by impact with trees and terrain.
Investigation Findings
The Norwegian Safety Investigation Authority conducted thorough examinations of technical, operational, and human factors. Investigators were unable to determine why the aircraft transitioned from straight and level flight to a sudden nose-down attitude. The steep descent was not characteristic of normal manoeuvring; it could have been unintentional or resulted from an aircraft problem. No technical faults were identified in the engine, ignition, or fuel systems, but the possibility of a partial or total loss of engine power could not be ruled out. The propeller was rotating and the engine was running at impact, but whether it produced full power could not be determined. The bang heard by witnesses may have indicated an engine anomaly. If the engine stopped at that moment, the pilot might have attempted a restart, but insufficient altitude likely prevented recovery. The pilot's limited forward field of view due to the passenger seated in the front may have contributed to not sighting trees in time.
Conclusion
The investigation concluded that the steep descent was not part of normal flight manoeuvres. No definitive cause was established, and the NSIA did not issue any safety recommendations.