What happened
On 30 October 2010, a Pierre Robin R2160 Alpha Sport, registration G-SACK, was performing aerobatic maneuvers at approximately 2,500 ft. During the flight, the pilot conducted a practice forced landing. While climbing back to altitude at roughly 1,000 ft, the engine began running roughly before failing completely.
Due to the low altitude and high energy, the pilot faced restricted landing options. Although the pilot intended to land in a field adjacent to the River Derwent, the aircraft's height made it difficult to reach the chosen site even with full flaps. Consequently, the pilot overshot the intended field and attempted to reach the next field across the river. This resulted in the aircraft ditching into the River Derwent. The aircraft sustained damage to one wing tip and subsequently filled with water, adopting a nose-low attitude. The pilot and passenger managed to exit the aircraft and reach the riverbank, where they were met by a friend who had been filming the aerobatics. Both occupants were transported to the hospital via air ambulance and sustained no injuries.
The investigation
Investigators examined the circumstances surrounding the engine failure and the subsequent ditching. The inquiry noted that the pilot had been practicing forced landings, which is a standard part of flight training and proficiency. The investigation also looked into reports from a passer-by who claimed to have seen the same aircraft performing low-level passes along the river recently. An inquiry at the operating flying club confirmed that the pilot was indeed operating G-SACK at the time of the accident.