History of Flight
At 1207 central daylight time on September 6, 2014, a Robinson R44 II helicopter, registration N699TQ, impacted a suspended static line near Macedonia, Iowa. The helicopter was operating under 14 CFR Part 137 as an aerial application flight. Day visual meteorological conditions prevailed, and no flight plan was filed. The local flight originated at an unknown time.
A witness approximately half a mile from the accident site reported hearing the helicopter before seeing it. The helicopter was flying north, entered the suspended lines, pitched upward, and then descended toward the ground. Fuel was observed leaking at the accident site. Another witness, about a quarter mile away, stated the helicopter was flying north at a height above larger transmission lines and made no apparent evasive action to avoid the lines. From his position, he could not see the smaller static line until contact. The static line stretched to the north until it broke, and the helicopter impacted the ground. No sparks or fire were observed. The engine sound changed after the wire strike, described as similar to a lawn mower going over a rock.
Power line maintenance employees reported that the larger transmission lines were not energized at the time of the accident. The smaller line struck was a static line, composed of seven strands of high-strength steel, measuring 3/8 inch thick. The tower structures were 111 feet tall and spaced 1,650 feet apart, with an estimated 25-foot vertical separation between the static lines and transmission lines.
The pilot's spraying partner stated they intended to spray from 1100 to 1800 that day. The partner, the accident pilot, and the operator completed paperwork for about two hours in preparation. The field sprayed prior to the accident was the fourth field of the day. The partner loaded the helicopter with 30 gallons of applicant and filled it with fuel, reporting no issues. After the spray flight, the partner drove about 17 miles (30 minutes) to meet the pilot at the next location, but the helicopter had already crashed upon arrival. He noted the absence of radio communication during the drive, which was unusual.
A GPS receiver recovered from the accident site was sent to the NTSB Vehicle Recorder Laboratory for data download.
Personnel Information
The pilot, age 26, held a commercial pilot certificate with ratings for rotorcraft-helicopter and instrument helicopter, as well as a flight instructor certificate. He was issued a first-class FAA medical certificate on February 27, 2014, with no limitations. On the medical application, he reported 1,500 total flight hours and 100 hours in the preceding six months. According to the operator, the pilot's flight experience included over 1,522 total rotorcraft hours and over 1,084 hours in the accident helicopter make and model. He had accumulated over 109 hours in the preceding 90 days and over 20 hours in the preceding 30 days, all in the accident make and model.
Aircraft Information
The helicopter was a Robinson R44 II, a single-engine light helicopter with skid landing gear, manufactured in 2004. It featured a semi-rigid two-bladed main rotor system and a two-bladed tail rotor, powered by a 205-horsepower Lycoming IO-540 reciprocating engine. The engine had accumulated 308 total hours and 2 hours since the last inspection. A 100-hour inspection was completed on August 25, 2014, at an airframe total time of 1,183 hours. The helicopter was equipped for agricultural spray operations.
Meteorological Information
At 1215, the automated weather observation at Council Bluffs Municipal Airport (CBF), located 11 miles west-northwest of the accident site, reported wind from 080° at 4 knots, visibility 10 miles, clear sky, temperature 66°F, dew point 50°F, and barometric pressure 30.30 inches of mercury.
Wreckage and Impact Information
The wreckage was located at GPS coordinates 41°10'57.2" N / 95°32'07.3" W, elevation 1,202 feet mean sea level. The area consisted of cultivated agricultural fields in one-mile squares, terraced with descending slopes from west to east. Several power lines ran east-west, intersecting the intended spray field and the field containing the wreckage. The lines were mounted on 111-foot-tall metal towers and consisted of three larger transmission lines beneath two static lines. The northern static line was found broken and lying on the ground, with signatures consistent with tension overload. The distance from the lines to the accident site was 240 feet on a north heading.
The main wreckage comprised the fuselage, tail boom, and tail rotor system. The main rotor system separated and came to rest about 75 feet north of the main wreckage. The main rotor blades were damaged but generally straight; one blade had a distinct cut near the hub, starting on the leading edge and extending inboard. After relocation to the owner's farm, examination revealed multiple structural failures consistent with impact with a wire and terrain. The passenger area and engine compartment were significantly compressed. The tail boom remained attached but was bent for transport. Flight control continuity could not be confirmed due to extensive damage. The application storage tank was broken open. The instrument panel showed impact damage but remained intact; the altimeter Kollsman window read 29.94.
Additional Information
The helicopter was equipped with a DynaNav DynaFlight AirAg-E GPS-based guidance and mapping system. Data was recorded on a compact flash drive at a variable rate determined by an algorithm. The unit sustained moderate impact damage. The compact flash card read normally, and data from 23 sessions from June 7, 2013, through September 6, 2014, was extracted. The accident flight was recorded from 17:03:12 to 17:07:19 UTC on September 6, 2014. Data showed the helicopter moving northeast initially, then westward, spraying in certain areas before proceeding north. During the operation, the helicopter flew between 1,142 and 1,342 feet MSL. Due to buffering, the recording may have ended before the accident. The final recorded points showed the helicopter headed north in a slight descent from 1,255 feet MSL, about 88 feet above the ground.
Medical and Pathological Information
The pilot initially survived the accident and was hospitalized; however, on September 11, 2014, he died as a result of the injuries sustained. An autopsy performed on September 13 attributed the cause of death to multiple blunt force injuries to the chest and abdomen. Forensic toxicology was negative.