McAllen, TX, USA
N3925A
EUROCOPTER EC120B
The pilot and the supplemental crewmember were dispatched to provide aerial support for an on-going border patrol mission. The mission was delayed, so the pilot decided to make a no-hover landing to an unfamiliar grass field and sit idle (to conserve fuel) until needed. On approach, the pilot had too much forward speed for the no-hover landing and transitioned to a slow, running landing. Upon touchdown, the pilot said he used full aft cyclic to control the maneuver but did not remember what he did with the collective. The helicopter slid about 34 feet then pitched forward causing the helicopter's lower wire strike protection system and the main rotor blades to strike the ground. According to the operator's aircraft standardization manual, during a running landing, the pilot has to hold the collective stationary after ground contact to avoid any rapid pitch reductions. The pilot reported that there were no mechanical problems prior to the accident. He said the accident could have been avoided if he had conducted an approach to hover followed by a vertical landing or executed a go-around and re-attempted a no-hover landing.
On October 4, 2011, approximately 1250 central daylight time, N3925A, a Eurocopter EC120B, sustained substantial damage while making a running landing to an unprepared grass field ten miles east of McAllen Miller International Airport (MFE), McAllen, Texas. The air interdiction agent (AIA) (the pilot) and the supplemental aircrew member (SAM) sustained minor injuries. The helicopter was registered to and operated by the Department of Homeland Security, Washington, DC. Visual meteorological conditions prevailed and no flight plan was filed for the Public Use flight conducted under 14 Code of Federal Regulations Part 91. The AIA and the SAM were dispatched to provide aerial support for an on-going 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) until needed. The AIA said he carried too much forward speed for the no-hover landing and transitioned to a slow, running landing instead. He said this was to avoid brown-out conditions. The helicopter touched down 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. 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 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. 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/model as the accident helicopter. His last Federal Aviation Administration (FAA) Second Class medical was issued on January 31, 2011.
The pilot's improper use of the collective while landing, which resulted in an unrecoverable forward pitching moment. Contributing to the accident was the pilot's improper decision not to go-around.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
