NTSB Factual Report

On June 25, 2009, at 1500 Pacific daylight time, a Robinson R44 II, N515DG, landed hard during a forced landing approximately 7 miles west-northwest of Lakeport, California. Cutting Edge Helicopters was operating the helicopter under the provisions of 14 Code of Federal Regulations Part 91. The certified flight instructor (CFI) and private pilot undergoing instruction (PUI) were not injured. The helicopter was substantially damaged. Visual meteorological conditions prevailed and no flight plan was filed.

The CFI reported that the helicopter had been fueled to capacity prior to takeoff. They were conducting a 180-degree autorotation with a power recovery. They entered the helicopter into a glide and as they made the turn, the CFI noticed that the oil and auxiliary fuel pump lights were on. The CFI then looked at the tachometer and attempted to increase the throttle. The power did not return so the CFI committed to a landing. During the landing, the main rotor blades impacted the tail boom.

The helicopter and engine were examined following their recovery from the accident site. The spark plugs were removed and examined. Their condition was consistent with normal operation when compared to a Champion Check-A-Plug chart. With the engine still installed on the helicopter and using the original fuel onboard the helicopter, it was powered. The engine test ran and no pre-impact anomalies were identified.

According to Robinson Helicopter Company (RHC) Safety Notice SN-38, Practice Autorotations Cause Many Training Accidents, “There have been instances where the engine has quit during practice autorotation. To avoid inadvertent engine stoppage, do not roll the throttle to full idle. Reduce throttle firmly for a small visible needle split, then hold throttle firmly to override governor. Recover immediately if engine is rough or engine RPM continues to drop.”

NTSB Probable Cause

A loss of engine power while maneuvering for undetermined reasons.