14 CFR Part 91: General Aviation
Monday, July 02, 2018
Robinson R22, registration:
Injuries: 2 Uninjured.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
On July 2, 2018, about 1445 central daylight time, a Robinson Helicopter Company R-22 Beta II helicopter, N830J, sustained substantial damage during a landing after a partial loss of engine power in the traffic pattern at Georgetown Municipal Airport (GTU), Georgetown, Texas. The left seat commercial pilot and the right seat certificated flight instructor (CFI) sustained no injury. The helicopter was registered to and operated by Veracity Aviation, LLC, Seguin, Texas under the provisions of Title 14 Code of Federal Regulations Part 91 as a visual flight rules instructional flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. The flight originated from GTU about 1400.
In a conversation with the National Transportation Safety Board investigator-in-charge on July 5, the CFI reported that the purpose of the local area flight was to conduct CFI training with the pilot. The pilot was in the process of working toward achieving his CFI rating. The flight initially consisted of maneuvers such as hovering autorotations and rapid decelerations over a sod area at the airport. The flight then progressed with stop-and-go landings involving normal takeoffs and concluding with normal approaches and steep approaches, while in the right traffic pattern for Kilo taxiway. The pilot was on the flight controls, demonstrating and explaining the maneuvers to the CFI.
While on the last traffic pattern iteration, on the downwind leg about 500 feet above ground level (agl) and about 70 knots, the CFI reported he was visually outside of the helicopter, scanning for traffic and clearing the helicopter for the base leg turn when he heard the low rotor revolutions per minute (rpm) horn activate. The CFI came on the flight controls and he immediately reduced the collective and applied throttle. The CFI heard the low rotor rpm horn cease and observed the low rotor rpm light extinguish, while he visually confirmed the engine and rotor rpm was about 97%. The CFI began the base leg turn and heard the low rotor rpm horn again. The CFI observed the tachometer and noticed that the engine and rotor rpm were decaying. The CFI assessed the situation and felt that the engine was not capable of maintaining the rotor rpm within safe operating limits and he entered an autorotation.
The CFI scanned the instruments and observed the airspeed was about 55 knots. He reported he could not hear noise emitting from the engine and surmised that the engine had ceased producing power. After the entry portion to the flare portion of the autorotation, the CFI reported that he was focused on maintaining the rotor rpm and maneuvering the helicopter to his selected landing area. About 35 feet agl, he began the flare to reduce the forward airspeed and the rate of descent. The helicopter touched down on a yard at a private residence, with a small amount of forward airspeed. The skids impacted a concrete driveway at the residence. The impact with the driveway resulted in the helicopter pitching nose low with the tail elevated, along with a right yaw. Both tail rotor blades impacted the ground, resulting in both blades becoming separated from the tail rotor gearbox. The vertical stabilizer sustained substantial damage from the ground impact, along with minor damage sustained to the tail rotor stinger and skid system. Once the helicopter came to rest, the CFI observed that the engine was at idle and performed an emergency shutdown. Both occupants egressed from the helicopter without further incident.
The CFI reported that the helicopter had an adequate amount of fuel for the flight and the helicopter had no known previous issues with the airframe or engine that would have precluded normal operation.
The wreckage was recovered from the private residence to the operator's hangar at GTU for a future examination of the helicopter.
The two-seat capacity helicopter, serial number 4236, was built in 2007. The helicopter was powered by a 4-cylinder, 145 horsepower Lycoming O-360-J2A carbureted engine.