Accident Overview
On October 4, 2011, at approximately 1250 central daylight time, a Eurocopter EC120B, registration N3925A, sustained substantial damage while making a running landing to an unprepared grass field ten miles east of McAllen Miller International Airport (MFE) in McAllen, Texas. The helicopter was registered to and operated by the Department of Homeland Security, Washington, D.C. Visual meteorological conditions prevailed, and no flight plan was filed for the Public Use flight conducted under 14 Code of Federal Regulations Part 91.
Sequence of Events
The air interdiction agent (AIA), who was the pilot, and the supplemental aircrew member (SAM) were dispatched to provide aerial support for an ongoing border patrol mission. When the AIA realized there would be a delay in the mission, he decided to make a no-hover landing in an unfamiliar grass field and sit idle to conserve fuel. The AIA stated that he carried too much forward speed for the no-hover landing and transitioned to a slow, running landing instead to avoid brown-out conditions. The helicopter touched down at a speed between 16 and 24 knots and slid forward approximately 34 feet before the helicopter began a forward pitching moment. The helicopter's wire strike protection system (WSPS) and the main rotor blades struck the ground. As the helicopter continued to pitch over, it began a counter-clockwise rotation and came to rest on its right side, severing the tail boom. The skids and main rotor blades were also damaged.
Pilot Actions
The pilot stated that during the landing he pulled the cyclic full aft but could not recall what he did with the collective. According to the operator’s aircraft standardization manual (ASM), during a running landing, the pilot should begin a slow deceleration by applying aft cyclic to approximately five degrees nose up and slightly lowering the collective to maintain a constant approach angle. The pilot should decelerate and arrive at an airspeed slightly above effective translational lift (ETL) and a height of ten feet above ground level simultaneously. After ground contact, the pilot must ensure the helicopter remains stable and the collective is held stationary to avoid any rapid pitch reductions until the termination of the ground run. The AIA reported that there were no mechanical problems prior to the accident. He said that the accident could have been prevented if he conducted an approach to hover followed by a vertical landing or made a go-around and re-attempted a no-hover landing.
Pilot Qualifications
The AIA held a commercial pilot certificate for airplane single-engine land and rotorcraft-helicopter. He reported a total of 4,517 total flight hours, of which 4,370 hours were in helicopters and 403 hours were in the same make and model as the accident helicopter. His last Federal Aviation Administration (FAA) Second Class medical was issued on January 31, 2011.