FTW02LA044

NTSB accident investigation · Bell 47G · Ardmore, OK · December 1, 2001

Accident · No injuriesLimited investigationFinal report
Date
December 1, 2001, 10:30 local (16:30 UTC)
Place
Ardmore, OK
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N5226Bell 47G
Weather
Visual (VMC) · Day
Status
Completed · report January 16, 2003
Report
Approved by Office Director
Parties
FAA FSDO
FAA report
20011201034399A
Case key
53850

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

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Probable cause

the flight instructor's selection of an unsuitable area for practicing a full touchdown autorotation, which resulted in a nose over. A contributing factor was the soft ground.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

On ground/water encounter with terrain/waterLanding - roll
Emergency procedure - simulatedPilot in command(cfi)
Unsuitable terrain or takeoff/landing/taxi area - selectedPilot in command(cfi)Cause
Terrain condition - softFactor
Nose overLanding - roll
Misc rotorcraft,main rotor/tail boom contact

Analysis

The student pilot had completed three power recovery autorotations to the south, and the flight instructor was to demonstrate a "full touchdown autorotation" to end the training session. The flight instructor initiated the autorotation at 1,500 feet msl and 60 knots to the airport's mid-field median. After slowing to 40 knots, the instructor began a flare to reduce the airspeed to 15-20 knots. At 10 feet agl, he pulled collective to cushion the landing. The helicopter touched down on the soft grassy area and slid for approximately 10 feet before starting to nose over. "The tail of the helicopter pitched upward into the blades, severing it." The helicopter rotated left approximately 270 degrees before coming to rest upright. The flight instructor stated that "weather had saturated the ground and caused the sod to be soft on the usual landing area. It was not visible from the helicopter."

Factual narrative

On December 1, 2001, at 1030 central standard time, a Bell 47G helicopter, N5226, was substantially damaged during a practice autorotational landing at the Ardmore Downtown Executive Airport near Ardmore, Oklahoma. The helicopter was registered to a private individual and operated by Versatile Helicopters, Inc., dba Versatile Aviation of Ardmore, Oklahoma. The flight instructor and the private pilot rated student were not injured. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 instructional flight. The local flight originated from the Ardmore Downtown Executive Airport, approximately one hour prior to the accident.

The student pilot had completed three power recovery autorotations to the south, and the flight instructor was to demonstrate "a full touchdown autorotation" to end the training session. The flight instructor initiated the autorotation at 1,500 feet msl and 60 knots to the mid-field median. After slowing to 40 knots, the instructor began a flare to reduce the airspeed to 15-20 knots. At 10 feet agl, he pulled collective to cushion the landing. The helicopter touched down on the soft grassy area and slid for approximately 10 feet before starting to nose over. "The tail of the helicopter pitched upward into the blades, severing it." The helicopter rotated left approximately 270 degrees before coming to rest upright.

The flight instructor stated that "weather had saturated the ground and caused the sod to be soft on the usual landing area. It was not visible from the helicopter."

Aircraft

Registration
N5226
Reported as
Bell 47G
Category
Helicopter
Serial number
37
Airframe hours
15,438
Engine
Franklin 6A-355-B1, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Registered owner
Versatile Helicopters, Inc.
Airworthiness certificate
Standard, Normal
Departed
1F0 · Ardmore, OK
Airport
1F0 · Ardmore Downtown Executive

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Flight instructor
Age
33
Injuries
None
Certificates
Flight instructor, Private, Commercial
Airplane ratings
Single-engine land
Medical
Class 3, Valid Medical--no waivers/lim.
Last flight review
August 21, 2001
Seat
Right
Flight hours
450 total
Role
Student pilot
Age
24
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Last flight review
September 26, 2000
Seat
Left

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
52 °F, dew point 43 °F
Altimeter
30.20 inHg
Observed at
1F0

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 N5226 · 4

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