WPR12LA107

NTSB accident investigation · Bell AH-1F · Coolidge, AZ · March 1, 2012

Accident · Minor injuriesLimited investigationFinal report
Date
March 1, 2012, 12:20 local (19:20 UTC)
Place
Coolidge, AZ
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N197LEBell AH-1F
Defining event
Maneuvering: Flight control sys malf/fail
Weather
Visual (VMC) · Day
Status
Completed · report July 13, 2015
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administrtion
FAA report
20120301003329A
Case key
82915

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

A flight control malfunction while maneuvering for reasons that could not be determined because postaccident examination revealed no evidence of a mechanical malfunction or failure that would have precluded normal operation.

Findings · 1

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.

Not determinedNot determined › Not determined · Unknown/Not determinedBell AH-1F: 1 caseAll aircraft: 2,247 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 pilot reported that he was conducting flybys to film a segment for a documentary. During his last run, he initiated a 150- to 180-degree climbing right turn to about 200 ft above the ground. After the turn, he attempted to neutralize the flight controls in preparation for a normal approach to land, but he was unable to move them. The helicopter remained in the same turn rate with the same collective pitch and cyclic input until ground impact. A postaccident examination of the helicopter revealed no evidence of preimpact mechanical malfunctions or failures that would have precluded normal operation. The reason for the flight control malfunction could not be determined.

Factual narrative

On March 01, 2012, at 1220 mountain standard time, N197LE, an experimental exhibition Bell AH-1F helicopter experienced a loss of directional control during maneuvering flight and impacted the ground at Coolidge Municipal Airport (P08), Coolidge, Arizona. The helicopter was operated by the Army Aviation Heritage Foundation and Museum, Inc., under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The pilot and mechanic received minor injuries; the helicopter sustained substantial damage. Visual meteorological conditions prevailed for the local area flight that departed P08 at an undetermined time. The pilot stated that the purpose of the flight was to film a segment for a documentary. The first flight of the filming sequence was uneventful. It lasted approximately 10 minutes and included helicopter flybys. The next filming sequence consisted of the accident helicopter and a vehicle in a race simulation. At 1205, a practice run began that terminated at the start/finish line. After crossing the finish line, the pilot initiated a climbing 150- to 180-degree right turn to an altitude of about 200 feet above the ground. He attempted to neutralize the controls in preparation for a normal approach for landing but was unable to move them. The helicopter remained in the same rate of turn, with the same collective pitch and cyclic input, until impact with the ground. The pilot further stated that, at impact, he tried to activate the emergency hydraulic switch. A postaccident examination by the Federal Aviation Administration airworthiness inspector revealed no mechanical failures or malfunctions that would have precluded normal operation. Neither the pilot nor the operator provided a completed NTSB Pilot/Operator Aircraft Accident ReportForm 6120.1.

Aircraft

Registration
N197LE
Reported as
Bell AH-1F
Category
Helicopter
Serial number
83-24197
Engine
Lycoming T53L-703, 1,400 horsepower, turbo shaft
Damage
Substantial damage
Flight
Business · Part 91
Airworthiness certificate
Special, Experimental (Special)
Departed
P08 · Coolidge, AZ
Destination
P08 · Coolidge, AZ
Flight plan
Unknown
Airport
P08 · Coolidge Municipal Airport

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
63
Injuries
Minor
Certificate
Commercial
Instrument ratings
Helicopter
Medical
Class 2, With waivers/limitations

Weather

Conditions
Visual (VMC) · Day
Wind
200° at 7 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
64 °F, dew point 25 °F
Altimeter
30.03 inHg
Observed at
CGZ, 17 nm away

Docket · 5

The files NTSB released with the investigation on June 15, 2015, on NTSB’s docket system: statements, records, photos and specialists’ reports. 5.5 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.