Sunday, May 09, 2021

Bell 47G-2, N5990: Accident occurred May 06, 2019 at Denton Enterprise Airport (KDTO), Denton County, Texas

Aviation Accident Final Report - National Transportation Safety Board

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Irving, Texas

Investigation Docket - National Transportation Safety Board:

Location: Denton, Texas
Accident Number: GAA19CA250
Date & Time: May 6, 2019, 10:20 Local
Registration: N5990
Aircraft: Bell 47G 
Aircraft Damage: Substantial
Defining Event: 
Injuries: 2 None
Flight Conducted Under: Part 91: General aviation - Instructional


The student pilot reported that he hovered the helicopter to the parking pad and landed with the helicopter's nose facing north. The skid placement on the parking pad was incorrect, and the flight instructor directed the student to reposition the helicopter about 3 ft to the left. The student brought the helicopter to a hover and repositioned it 3 ft to the left.

However, before the student established a descent and landed, the helicopter encountered a tailwind gust. The nose pitched down, the rotor rpm decreased, and the helicopter traveled about 75 ft forward. The skids contacted the ground hard, and the helicopter came to an abrupt stop, upright and facing downslope. The main rotor blades struck the tail rotor drive shaft and the tailboom. The tail rotor gear box and the tail rotor separated from the helicopter.

The helicopter sustained substantial damage to the tail rotor drive system, the tailboom, and the main rotor blades.

The pilot reported that there were no mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

The airport's METAR reported that, about the time of the accident, the wind was from 180° at 15 knots and that the cloud layer was broken at 800 ft.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The flight instructor's improper decision to instruct the student pilot to establish a hover and reposition the helicopter with a tailwind, which resulted in the student pilot's loss of pitch control. 


Personnel issues Decision making/judgment - Instructor/check pilot
Personnel issues Aircraft control - Student/instructed pilot
Aircraft Pitch control - Not attained/maintained
Environmental issues Tailwind - Decision related to condition
Environmental issues Tailwind - Effect on operation

Factual Information

History of Flight

Maneuvering-hover Other weather encounter
Maneuvering-hover Loss of control in flight
Landing Hard landing
Landing Collision with terr/obj (non-CFIT)
Landing Part(s) separation from AC

Pilot Information

Certificate: Student 
Age: 54,Male
Airplane Rating(s): None 
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): None 
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 Without waivers/limitations
Last FAA Medical Exam: November 15, 2018
Occupational Pilot: No 
Last Flight Review or Equivalent:
Flight Time: (Estimated) 24 hours (Total, all aircraft), 15 hours (Total, this make and model), 24 hours (Pilot In Command, all aircraft), 15 hours (Last 90 days, all aircraft), 5 hours (Last 30 days, all aircraft), 1 hours (Last 24 hours, all aircraft)

Flight instructor Information

Certificate: Airline transport; Flight engineer; Flight instructor
Age: 61, Male
Airplane Rating(s): Single-engine land; Single-engine sea; Multi-engine land
Seat Occupied: Right
Other Aircraft Rating(s): Helicopter
Restraint Used: Lap only
Instrument Rating(s): Airplane; Helicopter
Second Pilot Present: Yes
Instructor Rating(s): Airplane multi-engine; Airplane single-engine; Helicopter;
Instrument airplane; Instrument helicopter
Toxicology Performed: No
Medical Certification: Class 1 With waivers/limitations 
Last FAA Medical Exam: January 30, 2019
Occupational Pilot: Yes 
Last Flight Review or Equivalent: February 7, 2019
Flight Time: (Estimated) 30000 hours (Total, all aircraft), 200 hours (Total, this make and model), 25000 hours (Pilot In Command, all aircraft), 100 hours (Last 90 days, all aircraft), 50 hours (Last 30 days, all aircraft), 10 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: Bell 
Registration: N5990
Model/Series: 47G 2 
Aircraft Category: Helicopter
Year of Manufacture: 1992
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 2396
Landing Gear Type: Skid 
Seats: 3
Date/Type of Last Inspection: June 7, 2018 Annual 
Certified Max Gross Wt.: 2450 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 3360.1 Hrs at time of accident
Engine Manufacturer: Lycoming
ELT: Not installed 
Engine Model/Series: VO-435-A1
Registered Owner:
Rated Power: 270 Horsepower
Operator: On file 
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual (VMC)
Condition of Light: Day
Observation Facility, Elevation: KDTO,642 ft msl
Distance from Accident Site: 0 Nautical Miles
Observation Time: 15:28 Local 
Direction from Accident Site: 348°
Lowest Cloud Condition: 
Visibility: 10 miles
Lowest Ceiling: Broken / 8000 ft AGL
Visibility (RVR):
Wind Speed/Gusts: 15 knots / 
Turbulence Type Forecast/Actual:  /
Wind Direction: 180° 
Turbulence Severity Forecast/Actual:  /
Altimeter Setting: 29.95 inches Hg 
Temperature/Dew Point: 25°C / 17°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: DENTON, TX (DTO)
Type of Flight Plan Filed: None
Destination: DENTON, TX (DTO) 
Type of Clearance: VFR
Departure Time: 09:00 Local 
Type of Airspace: Class D

Airport Information

Airport: Denton Enterprise DTO
Runway Surface Type: Asphalt
Airport Elevation: 642 ft msl
Runway Surface Condition: Dry
Runway Used: 
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: None

Wreckage and Impact Information

Crew Injuries: 2 None
Aircraft Damage: Substantial
Passenger Injuries:
Aircraft Fire: None
Ground Injuries: N/A 
Aircraft Explosion: None
Total Injuries: 2 None
Latitude, Longitude: 33.20222,-97.198059(est)

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