- Date
- February 24, 2021, 22:59 local (Feb 25, 2021, 04:59 UTC)
- Place
- Tulsa, OK · airport taxiway
- Injuries
- 3 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N259AMEurocopter EC130
- Defining event
- Landing: Loss of tail rotor effectiveness
- Weather
- Visual (VMC) · Night
- Status
- Completed
- Report
- Approved by Office Director
- Investigation class
- Class 4 - Basic report with no Prelim publish
- NTSB office
- Central Region
- Parties
- Federal Aviation Administration, Oklahoma City FSDO, Air Methods
- Case key
- 102733
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 improper decision to approach the airport and enter a low altitude hover with a gusting quartering tailwind, which resulted in a loss of tail rotor effectiveness during a turn at a low altitude.
Findings · 6
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
After a west-southwest approach to the airport the pilot entered a low altitude hover near a taxiway intersection where he intended to turn left and join a north/south taxiway before continuing in a hover taxi south toward the ramp. During the counterclockwise turn to join the taxiway, the helicopter’s yaw rate increased as the tail passed through the north-northeast wind. The pilot allowed the helicopter to continue in the turn, despite an increasing left yaw rate, until the nose of the helicopter had realigned with the wind. However, at that point, he was unable to stop the counterclockwise rotation and the helicopter completed at least 2 revolutions before a landing skid struck the ground and the helicopter spun off the taxiway into a grass easement. The pilot and two medical personnel were not injured. The horizontal stabilizer attach fitting on the tail boom was fractured and required replacement. The operator did not report any mechanical malfunctions with the helicopter that would have precluded normal operation. According to a weather report issued about 6 minutes before the accident, the surface wind at the airport was from north-northeast at 8 knots. During the subsequent hour, the wind direction remained unchanged, but the wind speed had increased to 11 knots with 17 knot gusts. A loss of tail rotor effectiveness likely occurred when the helicopter encountered a wind gust during the left turn, which resulted in an increasing counterclockwise yaw rate that the pilot was unable to control.
Aircraft
- Registration
- N259AM
- Reported as
- Eurocopter EC130 (B4)
- Category
- Helicopter
- Serial number
- 7050
- Built
- 2011
- Airframe hours
- 4,050.4
- Engine
- Turbomeca Arriel 2B1, 747 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Part 135
- Operator
- Air Methods Corporation
- Registered owner
- Air Methods Corporation
- Airworthiness certificate
- Standard, Normal
- Last inspection
- AAIP · February 24, 2021
- Departed
- 4OK3 · Tulsa, OK
- Destination
- Same as departure
- Flight plan
- VFR
- Airport
- RVS · Richard Lloyd Jones, Jr.
- Equipment
- ADS-B, Satellite tracking device
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
- 56
- Injuries
- None
- Certificate
- Commercial
- Airplane ratings
- Single-engine land
- Instrument ratings
- Airplane, Helicopter
- Medical
- Class 2, Without waivers/limitations
- Last flight review
- April 5, 2020
- Seat
- Left
- Flight hours
- 4,587 total · 451 in this make and model · 18 in the last 90 days · 9 in the last 30 days · 1 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Night
- Wind
- 20° at 8 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 43 °F, dew point 30 °F
- Altimeter
- 30.29 inHg
- Observed at
- RVS
- METAR
- METAR KRVS 250453Z AUTO 02008KT 10SM CLR 06/M01 A3029 RMK AO2 SLP263 T00611006=
Docket · 9
The files NTSB released with the investigation on August 26, 2021, on NTSB’s docket system: statements, records, photos and specialists’ reports. 7.6 MB in all.