CEN19FA160

NTSB accident investigation · Robinson R44 · Cass, AR · June 3, 2019

Accident · FatalClass 3 · FieldFinal report
Date
June 2, 2019, 19:50 local (Jun 3, 2019, 00:50 UTC)
Place
Cass, AR
Injuries
3 fatal, 1 serious
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N41351Robinson R44
Defining event
Maneuvering-low-alt flying: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Central Region
Parties
FAA FSDO, Lycoming Engines, Robinson Helicopters
FAA report
20190602005609A
Case key
99538

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

A loss of engine power for reasons that could not be determined based on the available information.

Findings · 1

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Performance/control parametersAircraft › Aircraft oper/perf/capability · Not attained/maintainedRobinson Helicopter R44 II: 25 casesAll aircraft: 1,269 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot and three passengers departed on a local sightseeing flight at a music festival. The helicopter impacted a densely wooded area and came to rest between trees on its right side. The surviving passenger stated to the media that the helicopter’s engine made sounds “like your car does when it runs out of fuel.” Examination of the helicopter at the accident site indicated evidence of main rotor blade rotation; however, damage to the engine drive system did not reveal evidence of engine power at the time of impact. Additionally, the oil pressure warning light bulb filament was found stretched consistent with illumination at the time of impact, which according to the helicopter’s operating handbook, may be one indication of a loss of engine power. About 5 gallons of fuel was drained from the helicopter following the accident, with no evidence of fuel contamination. Examination of the airframe, flight controls, and engine revealed no evidence of any preimpact mechanical anomalies that would have precluded normal operation.

Factual narrative

The helicopter’s most recent inspection was a combined 2,200 hour overhaul, 100-hour, and annual inspection, completed on May 6, 2019. As part of this inspection, the engine was removed, overhauled, and reinstalled on the helicopter. According to the helicopter’s type certificate data sheet, the unusable fuel quantity was 1 gallon. R44 Emergency Procedures The pilot operating handbook for the helicopter, Section 3, Emergency Procedures, Power Failure – General, stated that an engine failure may be indicated by a change in noise level, nose left yaw, an oil pressure light, or decreasing engine rpm. On June 2, 2019, about 1950 central daylight time, a Robinson R44 II helicopter, N41351, was substantially damaged when it was involved in an accident near Cass, Arkansas. The pilot and two passengers were fatally injured, and one passenger survived with serious injuries. The helicopter was operated as a Title 14 Code of Federal Regulations Part 91 sightseeing flight. The helicopter flew passengers from a local music festival over the densely wooded area to the south of the performance arena. The helicopter was reported overdue and was located by search and rescue crews in a densely wooded area of the Ozark National Forest. There were no witnesses to the accident. A witness recalled seeing the helicopter while camping at the music festival. He saw the helicopter flying in an area different from the previous flights. He saw the helicopter’s nose pitch “dramatically” up. The helicopter climbed and then its climb stopped, sliding backwards tail first before the nose of the helicopter pitched rapidly down. The helicopter then entered a right turn and descended out of his view. He did not witness an impact and did not know about the accident until after viewing news reports. It is unknown if this was the accident sequence or if he witnessed a previous flight. The survivor of the accident was unable to provide a statement to investigators. During media interviews he stated that “the helicopter started chugging like your car does when it runs out of fuel. The engine cut and we started dropping.” A review of Automatic Dependent Surveillance – Broadcast (ADS-B) information captured numerous sporadic points of multiple flights flown on the day of the accident. The last recorded points captured the helicopter in a left turn about 200-300 ft above ground level at a groundspeed between 55 and 70 knots. The final point was about 250 yards from the accident site. An autopsy was conducted on the pilot by the Arkansas State Crime Laboratory. The cause of death was multiple injuries and the manner of death was ruled an accident. Toxicology testing was conducted by the FAA Forensic Sciences Laboratory. Testing was negative for carbon monoxide, cyanide, and ethanol. Hydroxychloroquine was detected in blood and in the liver. The pilot’s logbooks were not available for review. On his most recent application for a Federal Aviation Administration (FAA) medical certificate,dated December 19, 2018, the pilot reported 5,000 total hours of flight experience with 200 hours in the preceding 6 months. The helicopter impacted a densely wooded area of the Ozark National Forest and came to rest between trees on its right side. The tailboom was fractured and bent to the right but remained attached via the tail rotor drive shaft. Damage to the helicopter was consistent with an impact with trees in a nose-low right bank. Several large branches at the site displayed cuts and a tree trunk exhibited 45° slash marks. About 5 gallons of fuel was drained from the fuel tank. Fuel collected at the firewall gascolator appeared clean and free of contaminants. The gascolator filter was clear of debris. All main rotor blade and tail rotor linkages remained secured. Flight control continuity was confirmed from the cockpit controls to the swash plate to the blade pitch change links. Continuity of the main rotor drive system was confirmed by manually rotating the main rotor blades. The frame tubing displayed impact marks from the engine belt pulley with no directional score marks on either surface. All engine drive belts remained in place and were not damaged. The attitude indicator displayed a right bank, and the airspeed indicator displayed about 88 knots. Several of the cockpit lights were impact damaged, of the remaining lights, the oil pressure warning light’s filament was stretched. Examination of the airframe revealed no evidence of any preimpact anomalies. Examination of the engine revealed no evidence of any preimpact anomalies. The fuel servo was removed and bench tested. No malfunctions were detected with the fuel servo.

Aircraft

Registration
N41351
Reported as
Robinson R44 (II)
Category
Helicopter
Serial number
12351
Built
2008
Airframe hours
2,246
Engine
Lycoming IO-540-AE1A5, 245 horsepower, reciprocating
Damage
Substantial damage
Flight
Other work use · Part 91
Operator
D & C Aviation Llc
Registered owner
D & C Aviation Llc
Airworthiness certificate
Standard, Normal
Last inspection
Annual · May 6, 2019 · 46.08 hours before

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
51
Injuries
Fatal
Certificate
Commercial
Instrument ratings
Helicopter
Medical
Class 2, With waivers/limitations
Seat
Right
Restraint
3-point
Toxicology
Performed
Flight hours
5,000 total

Weather

Conditions
Visual (VMC) · Day
Wind
100° at 4 knots
Visibility
10 statute miles
Lowest ceiling
10,000 ft overcast
Temperature
70 °F, dew point 66 °F
Altimeter
29.70 inHg
Observed at
KFSM, 36 nm away

Docket · 12

The files NTSB released with the investigation on November 9, 2021, on NTSB’s docket system: statements, records, photos and specialists’ reports. 41.1 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.