History of the Flight
On 30 January 2018 at 1045 UTC, a student pilot flying a Robinson R22 Beta, registration G-CTRL, was undertaking his first solo flight at Nottingham Heliport. The instructor had assessed the student as competent after a 55-minute training flight with numerous takeoffs and landings. Before the solo, the instructor reminded the student that without an instructor in the left seat, the helicopter’s centre of gravity would shift right and aft, requiring the cyclic to be positioned left and forward to compensate, and that gentle control movements should be used during lift-off.
The instructor moved to a safe distance and signalled the pilot to lift off. The pilot adjusted the cyclic to what he thought was the correct position and raised the collective lever. He used available visual cues and made appropriate control adjustments but was unable to prevent the helicopter from rolling quickly onto its right side. The instructor reported that the pilot maintained directional control through correct yaw pedal use but did not apply sufficient left cyclic to compensate for the changed centre of gravity. The helicopter rolled onto its right side, and the rotor blades stopped when they struck the grass.
The instructor approached the helicopter and found the pilot trapped in his seat with minor injuries to his hands. He helped the pilot climb out through the left doorway before the heliport rescue service arrived. The instructor then switched off the fuel and electrical supplies.
Aircraft Information
The Pilots’ Operating Handbook and Rotorcraft Flight Manual for G-CTRL includes Robinson Helicopter’s Safety Notice SN-9, which discusses dynamic rollover. The notice, revised in June 1994, states: “A dynamic rollover can occur whenever the landing gear contacts a fixed object, forcing the aircraft to pivot about the object instead of about its own center of gravity… Once started, dynamic rollover cannot be stopped by application of opposite cyclic alone… Quickly applying down collective is the most effective way to stop dynamic rollover.” It advises using a two-step lift-off: “Pull in just enough collective to be light on the skids and feel for equilibrium, then gently lift the helicopter into the air.” This technique is required by EASA for training providers.
Other Information
The AAIB reported four other accidents in the previous 10 years involving dynamic rollover, three occurring during a student pilot’s first or second solo flight in a Robinson R22 Beta (G-SBUT in 2009, G-BYCF in 2014, G-DEFY in 2016) and one during a student’s first solo flight on type in a Robinson R66 (G-LROK in 2016). The European Helicopter Safety Team (EHEST) has produced educational leaflets, including HE-1 “Safety Considerations,” which covers dynamic rollover and avoidance techniques.