Aircraft Accident/Incident Report

Cherokee, Alabama 35616
Sunday, December 30, 2007 3:06 CST

NTSB Narrative Summary Released at Completion of Accident

The helicopter was maintaining a searchlight on a lost hunter as ground personnel attempted to execute a rescue. During the maneuver, the pilot was flying in an out-of-ground-effect hover, or very slow flight below effective translational lift, about 100 to 150 feet above the trees. The maneuver was contrary to the operations manual, which required a minimum altitude of 500 feet above ground level for night searches. It was also contrary to the operations manual as the maneuver fell inside the height-velocity diagram curve, published in the make and model rotorcraft flight manual (RFM). In addition, a company flight data analyst in the communications center was attempting to persuade the pilot to terminate the search due to safety concerns as the helicopter was flying low and slow. The helicopter began to spin right and descend into trees, consistent with loss of tail rotor effectiveness (LTE). During the spin, witnesses reported an engine noise increase and "fireball" coming from the exhaust, most likely as a result of an over-speed/over-temperature condition as the pilot increased engine power attempting to recover from the spin. Review of the RFM did not reveal any information on LTE; however, the operator maintained an LTE training program, which the pilot had completed. Additionally, the Federal Aviation Administration had previously published Advisory Circular (AC) 90-95, which stated that LTE is not related to a maintenance malfunction and may occur in varying degrees in all single main rotor helicopters at airspeeds less than 30 knots. The AC further stated that flight operations at low altitude and low airspeed are particularly susceptible to LTE, with greater susceptibility in right turns. Examination of the wreckage did not reveal any pre-impact mechanical malfunctions.

NTSB Probable Cause Narrative

The pilot's failure to maintain control of the helicopter during an out-of-ground-effect hover. Contributing to the accident was a loss of tail rotor effectiveness.

Event Information

Type of Event Accident
Event Date 12/30/2007
Event Day of the Week Sunday
Time of Event 306
Event Time Zone Central Standard Time
Event City Cherokee
Event State ALABAMA
Event Country --
Zipcode of the event site 35616
Event Date Year 2007
Event Date Month 12
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 344119N
Event Location Longitude 0875512W
Event Location Airport --
Event Location Nearest Airport ID --
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness --
Investigator's weather source Weather Observation Facility
Time of the weather observation 253 Central Standard Time
Direction of event from weather observation facility (degrees) 90
Weather Observation Facility ID MSL
Elevation of weather observation facility 550
Distance of event from weather observation facility (units?) 15
Time Zone of the weather observation CST
Lighting Conditions Night
Lowest Ceiling Height 7500
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions --
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 5
Air Temperature at event time (in degrees celsius) 5
Dew Point at event time (in degress fahrenheit) 4
Wind Direction (degrees magnetic) --
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) --
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30.02
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal 3
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 3
Investigating Agency NTSB
NTSB Docket Number (internal use) 24918
NTSB Notification Source FAA Southern Region ROC
NTSB Notification Date Dec 30 2007 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information --
Date of most recent change to record Jan 14 2009 2:20PM
User who most recently changed record broda
Basic weather conditions Visual Meteorological Cond
FAA District Office Birmigham, AL

Aircraft Involved

Aircraft #1

Aircraft Registration Number N109AE
NTSB Number NYC08FA071
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed Company VFR
Flight plan Was Activated? Yes
Damage Substantial
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name BELL
Aircraft Model 206L-3
Aircraft Series Identifier --
Aircraft Serial Number 51317
Certified Max Gross Weight 4150
Aircraft Category Helicopter
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 4
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection AAIP
Date of Last Inspection Dec 1 2007 12:00AM
Airframe hours since last inspection 5
Airframe Hours 5092
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type Unknown
Aircraft Owner Name Air Evac EMS Inc.
Aircraft Owner Street Address --
Aircraft Owner City West Plains
Aircraft Owner State MO
Aircraft Owner Country USA
Aircraft Owner Zipcode 65775
Operator is an individual? No
Operator Name Air Evac EMS Inc.
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address --
Operator City West Plains
Operator State MO
Operator Country USA
Operator Zip code 65775
Operator Code EVCA
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Other Work Use
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code NONE
Departure City Muscle Shoals
Departure State AL
Departure Country USA
Departure Time 151
Departure Time Zone CST
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code --
Destination City --
Destination State --
Destination Country USA
Specific Phase of Flight Maneuvering
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Dec 3 2008 10:09AM
User who most recently changed record kenj
Since inspection or accident Time of Accident
Event Location Runway Number and Location N/A
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight Yes
Medical Flight Discretionary