Background
The accident occurred during a ferry flight from Prague, Czech Republic, to Karlskrona, Sweden. The aircraft had just returned from a flight to France. The pilot in command (PIC) was on her first flight of the day. After landing, the original co-pilot left and was replaced by a co-pilot who had already flown two flights totaling 1 hour 40 minutes earlier that day. The aircraft departed Prague at 2008 hrs with no passengers, operating under Instrument Flight Rules.
Flight Sequence
The co-pilot was the pilot flying. The flight was conducted manually with no autopilot engaged. Shortly after takeoff from runway 31, the aircraft turned north and climbed. At 2014:16 hrs, the PIC commented, "I didn't fly night time for long time." The co-pilot then asked if she had experienced a roll during night, leading to a discussion about performing rolls. The conversation referenced "Bravo" doing rolls faster with ailerons but spoilers being slower.
At 2015:00 hrs, ATC Prague instructed the crew to climb to FL260 and level off above DEKOV. The instruction was repeated at 2015:33 hrs and acknowledged by the PIC at 2015:40 hrs. Between 2017:10 and 2017:20 hrs, the aircraft rolled longitudinally: first left to 30° bank, then right to 20° bank, returning to level. The PIC responded, "Let's go, we are already high enough, you nettle me - come on."
At 2017:22 hrs, ATC Prague handed off to ATC Munich, which instructed the crew to climb to FL330 at 2018:36 hrs. The crew acknowledged. Between 2018:51 and 2019:00 hrs, the PIC asked if the altitude was sufficient for a maneuver, and the co-pilot confirmed.
Final Maneuvers
At 2019:00 hrs, the aircraft leveled at FL270. At 2019:05 hrs, the nose pitched up to about 14°. At 2019:09 hrs, the aircraft rolled right, reaching inverted flight within 4 seconds, and another 90° in the next 4 seconds. The heading swung east, then south, then west. During the roll, the pitch angle decreased to nearly -85°, indicating a near-vertical dive. Airspeed increased significantly. The aircraft crashed near Reinhardtsdorf-Schöna, Saxon Switzerland, about 500 meters north of the Czech border.
Probable Cause
The official investigation determined that the accident was due to: "The crew tried to conduct a flight manoeuvre (roll) which is not part of commercial air transport" and "The crew suffered loss of spatial orientation and subsequently did no longer have the ability to recover the flight attitude." Contributing factors included the pilots not being trained in aerobatics, night conditions with no visual references, a crew relationship that led to unprofessional behavior, and the aircraft not being designed or certified for aerobatics.