WPR16LA069

NTSB accident investigation · Bell 47G 3B 1 · Carson City, NV · February 13, 2016

Accident · Minor injuriesLimited investigationFinal report
Date
February 13, 2016, 15:00 local (23:00 UTC)
Place
Carson City, NV
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N1181WBell 47G 3B 1
Defining event
Landing-flare/touchdown: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report August 16, 2016
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
FAA Reno FSDO
FAA report
20160213008159A
Case key
92715

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 failure to maintain sufficient main rotor rpm, which resulted in a loss of helicopter control and a dynamic rollover.

Findings · 5

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.

Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotBell 47G-3B-1: 6 casesAll aircraft: 9,295 casesProbable cause
Use of equip/info: use of equip/systemPersonnel issues › Task performance · PilotBell 47G-3B-1: 2 casesAll aircraft: 1,391 casesProbable cause
Performance/control parametersAircraft › Aircraft oper/perf/capability · Not attained/maintainedBell 47G-3B-1: 3 casesAll aircraft: 1,269 casesProbable cause
Main rotor systemAircraft › Aircraft propeller/rotor · Incorrect use/operationBell 47G-3B-1: 1 caseAll aircraft: 25 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 private pilot was practicing takeoffs and landings to a taxiway. The pilot reported that, during his fourth landing attempt and as he was transitioning to a hover, he noticed that the helicopter's main rotor rpm was slightly low, and he attempted to increase the rpm by adding power. However, the helicopter did not respond and settled onto the taxiway. The pilot then raised the collective to bring the helicopter back to a hover, but the rotor rpm was still low. The pilot continued to try and add power, but the helicopter drifted right, and the right skid then contacted the ground off the side of the taxiway, which resulted in a dynamic rollover and substantial damage to the airframe and rotor blades. The pilot stated that he was new to this type of helicopter, and it is likely that he allowed the main rotor rpm to decay to a point from which he was unable to recover. He stated that there were no preaccident mechanical anomalies with the helicopter that would have precluded normal operation.

Factual narrative

On February 13, 2016, about 1500 Pacific standard time, a Bell 47G-3B-1 helicopter, N1181W, sustained substantial damage while attempting to land at the Carson Airport, Carson City, Nevada. The private pilot and the pilot-rated passenger sustained minor injuries. The helicopter was registered to and operated by the pilot as a local flight under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the flight, and no flight plan was filed. The flight originated from the Carson Airport about 1315. In a written statement, the pilot reported that he had accomplished three previous take off and landings, and the helicopter was operating normally. On the fourth landing attempt, as he was transitioning to a hover, he noticed that the rotor RPM was slightly low. He attempted to raise the RPM by adding power, but did not get a response, and the helicopter settled onto the taxiway. He then pulled up on the collective to come back into a hover, but the rotor RPM was still low. He continued to try and raise the rotor RPM, but the helicopter started to yaw and drift to the right, and the right hand skid touched the ground off of the right side of the taxiway, initiating a dynamic rollover. The helicopter rolled onto its right side and came to rest in the dirt on the side of the taxiway. The pilot stated that he was new to this helicopter, and it was likely that he allowed the rotor RPM to decay to a point that he was unable to recover. He stated that there were no preaccident mechanical anomalies with the helicopter that would have precluded normal operation.

Aircraft

Registration
N1181W
Reported as
Bell 47G 3B 1 (T)
Category
Helicopter
Serial number
2948
Built
1966
Airframe hours
6,222.5
Engine
Lycoming TVO-435-B1A, 270 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · January 1, 2016 · 1 hours before
Departed
CXP · Carson City, NV
Destination
CXP · Carson City, NV
Airport
CXP · Carson

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
45
Injuries
Minor
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Without waivers/limitations
Last flight review
September 24, 2014
Seat
Left
Restraint
4-point
Flight hours
393 total · 12 in this make and model · 217 as pilot in command · 13 in the last 90 days · 5 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
350° at 3 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
63 °F, dew point 7 °F
Altimeter
30.25 inHg
Observed at
KCXP, 1 nm away

Docket · 1

The files NTSB released with the investigation on May 18, 2016, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.7 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.

Other investigations on N1181W · 2

Matched to the same aircraft by N-number and date.