- Date
- March 11, 2023, 15:30 local (21:30 UTC)
- Place
- De Kalb, TX · field
- Injuries
- 1 serious, 1 minor, 2 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N4164TRobinson Helicopter R44
- Defining event
- Maneuvering-low-alt flying: Loss of control in flight
- Weather
- Visual (VMC) · Day
- Status
- Completed
- Report
- Approved by Office Director
- Investigation class
- Class 3
- NTSB office
- Central Region
- Parties
- FAA Flight Standards
- Case key
- 106877
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
The pilot’s inability to maintain control of the helicopter due to his failure to maintain rotor speed. Contributing to the accident was the failure of the helicopter’s low rotor speed warning system.
Findings · 3
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.
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 flight was conducted to hunt feral hogs. The pilot reported that a group of hogs had entered a large field, and he lowered the collective to maneuver the helicopter closer. When he lowered the collective, he perceived a loss of engine and rotor speed. The helicopter immediately began to lose lift. Once the pilot realized that he could not recover the helicopter, he attempted a running (skid-on) landing. However, the landing skids got stuck in the muddy field, the helicopter rocked forward, and the main rotor blades struck the ground causing the aircraft to roll over. The pilot reported the low rotor speed warning did not activate when the rotor speed started to decay. He also stated that all required preflight checklists were complied with before the flight began and no anomalies were noted. A postrecovery examination was unremarkable with exception of the low rotor warning system, which was not operational at the time of the examination. Specifically, the warning system did not activate when the collective control was brought off the low pitch stop and increased to full travel. The reason for the failure of the low rotor warning system was not determined.
Factual narrative
On March 11, 2023, about 1530 central standard time, a Robinson Helicopter R-44, N4164T, was substantially damaged when it was involved in an accident near De Kalb, Texas. The pilot and one passenger were not injured, a second passenger sustained minor injuries, and a third passenger was seriously injured. The helicopter was operated as a Title 14 Code of Federal Regulations Part 91 aerial observation flight. The flight was conducted to hunt feral hogs. The pilot reported that a group of hogs had entered a large field, and he lowered the collective to maneuver the helicopter closer. When he lowered the collective, he perceived a loss of engine and rotor speed. The helicopter immediately began to lose lift. Once the pilot realized that he could not recover the helicopter, he attempted a running (skid-on) landing. However, the landing skids got stuck in the muddy field, the helicopter rocked forward, and the main rotor blades struck the ground causing the aircraft to roll over. The pilot reported the low rotor speed warning did not activate when the rotor speed started to decay. He also stated that all required preflight checklists were complied with before the flight began and no anomalies were noted. The helicopter sustained damage to the fuselage, main rotor blades, and tail boom. The aft portion of the tail boom, with the tail rotor assembly attached, was separated from the remainder of the airframe. It was located adjacent to the fuselage at the accident site. Postrecovery airframe and engine examinations, which included an 8-minute engine run, did not reveal any evidence of an in-flight structural failure, a flight control malfunction, or an inability of the engine to produce rated power. Although, the separated portion of the tail boom and tail rotor assembly were present at the accident site, they were not with the wreckage when recovered. The postrecovery examinations were unremarkable with exception of the low rotor warning system, which was not operational at the time of the examination. Specifically, the warning system did not activate when the collective control was brought off the low pitch stop and increased to full travel. The low rotor warning indicator bulb illuminated, and the warning horn emitted an audible sound when electrical current was applied. The reason for the failure of the low rotor warning system was not determined.
Aircraft
- Registration
- N4164T
- Reported as
- Robinson Helicopter R44
- Category
- Helicopter
- Serial number
- 1882
- Built
- 2008
- Airframe hours
- 2,065.3
- Engine
- Lycoming O-540-F1B5, 260 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial observation · Part 91
- Operator
- Hotel Sierra Aviation LLC, doing business as N/A
- Registered owner
- Hotel Sierra Aviation LLC
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · December 10, 2022 · 16.9 hours before
- Departed
- PVT · Haworth, OK
- Destination
- PVT · Haworth, OK
- Airport
- N/A · N/A
- Equipment
- ADS-B
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
- 38
- Injuries
- None
- Certificate
- Private
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 2, Without waivers/limitations
- Last flight review
- November 2, 2022
- Seat
- Rear
- Restraint
- 3-point
- Flight hours
- 1,972 total · 355 in this make and model · 1,750 as pilot in command · 135 in the last 90 days · 70 in the last 30 days · 10 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 190° at 8 knots
- Visibility
- 9 statute miles
- Lowest ceiling
- 2,700 ft broken
- Temperature
- 72 °F, dew point 63 °F
- Altimeter
- 29.62 inHg
- Observed at
- KTXK, 31 nm away
- METAR
- METAR KTXK 112153Z 19008KT 9SM SCT020 BKN027 OVC036 22/17 A2962
Docket · 10
The files NTSB released with the investigation on January 2, 2025, on NTSB’s docket system: statements, records, photos and specialists’ reports. 96.6 MB in all.