Aviation Accident Summaries

Aviation Accident Summary CEN11FA468

Rising Sun, IN, USA

Aircraft #1

N42333

ROBINSON HELICOPTER COMPANY R44 II

Analysis

The noninstrument-rated pilot contacted approach control and requested clearance through class B airspace with visual flight rules (VFR) radar service to his destination. About 7 minutes later, the pilot reported that he needed to descend because he was "getting into too many clouds." The approach controller approved the VFR descent and instructed the pilot to maintain VFR at or below 2,000 feet. About 6 minutes later, radar data were lost. Recorded radar track data indicated that the helicopter was on a northwest heading and then turned west, that the helicopter's altitude varied between 1,100 to 1,300 feet above ground level, and that the helicopter appeared to be in a right turn before impact. The helicopter impacted trees near the top of a ridgeline located about 0.3 mile west of the Ohio River at an elevation of about 700 feet. The Cincinnati/Northern Kentucky International Airport, located about 13 nautical miles northeast of the accident site, reported 4 miles visibility, haze, and scattered clouds at 1,100 feet. Witnesses reported dense ground fog along the river and on the ridgeline near the accident site at the time of the accident. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Based on the pilot's inexperience, the radar data, and the reduced visibility at the time of the accident, it is likely that the he experienced spatial disorientation, which led to his failure to maintain clearance from the terrain.

Factual Information

HISTORY OF FLIGHTOn July 9, 2011, about 0927 eastern daylight time, a Robinson R44 II, N42333, sustained substantial damage when it impacted trees and terrain near Rising Sun, Indiana. The pilot was fatally injured. The helicopter was owned and operated by the pilot as a personal flight under the provisions of the 14 Code of Federal Regulations Part 91. The flight departed from the Georgetown Scott County Airport (27K), Georgetown, Kentucky, about 0900, and was en route to the Anderson Municipal Airport (AID), Anderson, Indiana. Visual meteorological conditions prevailed at the time of the accident. No flight plan was filed. The pilot contacted the Cincinnati (CVG) approach control about 0911 requesting clearance through the CVG class B airspace with visual flight rules (VFR) radar service to AID. The controller instructed the pilot to squawk code 0432, and about 0912 advised the pilot of radar contact 25 miles south of CVG. The pilot stated that he was proceeding direct to AID on a course of 339 degrees. About 0919, the pilot reported that he needed to descend because, "…I'm getting into too many clouds." The controller approved the VFR descent, and instructed the pilot to maintain VFR at or below 2,000 feet. According to recorded radar data, the last target for the helicopter was seen about 0924. The controller advised the pilot, "…radar services lost" about 0925. About 0929, a commercial airliner advised the CVG approach control that he was receiving a, "…beacon on guard." (Emergency frequency 121.5 is also referred to as "guard" frequency) Radar track data indicated that the helicopter was on a northwest heading until it crossed an area which had a 650 foot tall smoke stack located about 12.5 nautical miles (nm) from CVG on a 226 degree bearing. The helicopter then turned about 90 degrees to the west. The radar data indicated that the helicopter's altitude varied between 1,100 to 1,300 feet above ground level, and it appeared that the helicopter was in a right turn prior to impact. The helicopter impacted trees on the top of a ridgeline located about 2 nm from the smoke stack, and about 0.3 miles west of the Ohio River. The elevation at the top of the ridgeline was about 700 feet. PERSONNEL INFORMATIONThe 60-year-old pilot held a private pilot's certificate with a helicopter rating. He had a total of about 575 flight hours, with about 42 hours in the make and model of the accident helicopter. He held a third class medical certificate that was issued in July 2010 with limitations for corrective lenses. AIRCRAFT INFORMATIONThe helicopter was a Robinson R44 II, serial number 12601, manufactured in 2010. The helicopter's maximum gross weight was 2,500 pounds and it seated four. The helicopter was powered by a 260-horsepower Lycoming IO-540-AE1A5 engine. The last annual maintenance inspection was conducted on May 3, 2011, and it had a total airframe and engine time of 493.4 hours. The helicopter had 517.4 hours at the time of the accident, and had operated 24 hours since the last maintenance inspection. METEOROLOGICAL INFORMATIONThe 0913 surface weather observation at the Cincinnati/Northern Kentucky International Airport (CVG), Covington, Kentucky, located about 13 nautical miles northeast of the accident site was: wind 090 degrees at 6 knots; 4 miles visibility; haze; scattered clouds at 1,100 feet; temperature 24 degrees Celsius (C), dew point 21 degrees C; altimeter 29.99 inches of mercury. Witnesses who lived near the accident site reported dense ground fog along the river and on the ridgeline near the accident site at the time of the accident. AIRPORT INFORMATIONThe helicopter was a Robinson R44 II, serial number 12601, manufactured in 2010. The helicopter's maximum gross weight was 2,500 pounds and it seated four. The helicopter was powered by a 260-horsepower Lycoming IO-540-AE1A5 engine. The last annual maintenance inspection was conducted on May 3, 2011, and it had a total airframe and engine time of 493.4 hours. The helicopter had 517.4 hours at the time of the accident, and had operated 24 hours since the last maintenance inspection. WRECKAGE AND IMPACT INFORMATIONThe helicopter impacted trees near the top of a ridgeline on a 325 degree magnetic heading, and the wreckage debris path covered about 333 feet. At the initial point of impact, the vertical stabilizer and horizontal stabilizer were found stuck in the top of a tree. Numerous tail rotor and tail boom parts were found in the debris field near the initial point of impact. The main wreckage, which included the fuselage, cockpit, engine, main rotor, and the front section of the tailboom, was located 261 feet down the hill. The instrument panel was found 333 feet from the initial impact point and near the end of the debris field. There was no postimpact ground fire. The airframe and engine were examined at the Rising Sun Fire Department, Rising Sun, Indiana. The examination of the airframe revealed drive train continuity from the engine to the transmission, the main rotor, the tail rotor flex plate couplings, and the tail rotor gear box. Flight control continuity from the helicopter's cockpit flight controls to their respective control surfaces on the main rotor and tail rotor was not established due to the extensive impact damage to the flight control tubes; however, all separations were consistent with overload failures. Impact signatures consistent with rotation were exhibited on the helicopter's lower sheave and V-belts, upper sheave and clutch, and flex plate assemblies. The tail rotor drive shaft was twisted. The main rotor blades exhibited extensive impact damage and were broken in numerous places. Both tail rotor blades were separated from the blade hub yokes. One of the tail rotor blades exhibited aft crushing of the leading edge. Engine control continuity from the cockpit to the engine was verified. The engine examination revealed that it could be rotated by hand. Crankshaft and camshaft continuity was observed and all valve train components were operating normally. The gears within the accessory gear section were observed rotating. All cylinders were inspected with a lighted borescope and no defects were noted. The spark plugs, fuel injector, engine driven fuel pump, fuel flow divider, magnetos, and oil system were checked and no pre-impact anomalies were observed. MEDICAL AND PATHOLOGICAL INFORMATIONAn autopsy of the pilot was conducted on July 10, 2011, at the Dearborn County Hospital, Lawrenceburg, Indiana. The "Cause of Death" was noted as "multiple blunt force injuries." A Forensic Toxicology Fatal Accident Report was prepared by the FAA Civil Aerospace Medical Institute. The results were negative for all substances tested.

Probable Cause and Findings

The noninstrument-rated pilot's decision to continue the visual flight rules flight into instrument meteorological conditions, which resulted in his spatial disorientation and failure to maintain clearance from terrain.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports