Aircraft Accident/Incident Report

Louisville, Kentucky 40231
Thursday, November 12, 1998 18:15 EST

NTSB Narrative Summary Released at Completion of Accident

The pilot reported that while in cruise at 700 feet AGL the helicopter yawed left, followed by a low rotor caution light being illuminated. The pilot executed an autorotation landing under dark night conditions to a flat, wet, muddy surface. During the landing the helicopter's skids began to dig in, and the helicopter began to nose over. The pilot applied aft cyclic in an effort to prevent the nose over during which the rotor blades impacted and severed the tailboom. Post-crash examination revealed 51 gallons of fuel aboard and no spreading deformation to the helicopter's skids. Further examination revealed that the 'B' nut on the PC air line from the power turbine governor to the fuel control unit was backed off about 2-3 'flats.' The engine was successfully operated in a test cell in an 'as received' condition. During subsequent engine runs, the 'B' nut was tightened and loosened to one flat with no variation in engine performance. The 'B' nut was also completely removed resulting in a stagnant start. According to the manufacturer, a breach in the PC air line will allow air pressure to bleed out and result in the fuel control unit automatically shifting to a minimum flow condition (less than idle). The test cell conditions may or may not have duplicated the vibratory conditions in the aircraft's airframe at the time of the power loss.

NTSB Probable Cause Narrative

A loose 'B' nut on the aircraft's PC Air line which resulted in fuel starvation, and the pilot's abrupt application of aft cyclic to prevent a nose over. Contributing factors were soft terrain and dark night conditions.

Event Information

Type of Event Accident
Event Date 11/12/1998
Event Day of the Week Thursday
Time of Event 1815
Event Time Zone Eastern Standard Time
Event City LOUISVILLE
Event State KENTUCKY
Event Country --
Zipcode of the event site 40231
Event Date Year 1998
Event Date Month 11
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
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 Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1748 Eastern Standard Time
Direction of event from weather observation facility (degrees) 98
Weather Observation Facility ID LOU
Elevation of weather observation facility 500
Distance of event from weather observation facility (units?) 6
Time Zone of the weather observation EST
Lighting Conditions Night/Dark
Lowest Ceiling Height 25000
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 7
Air Temperature at event time (in degrees celsius) 11
Dew Point at event time (in degress fahrenheit) -3
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 1
Injury Total None 2
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 1799
NTSB Notification Source --
NTSB Notification Date Nov 12 1998 12:00AM
NTSB Notification Time 2330
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 11 2000 11:53AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N32KY
NTSB Number IAD99LA015
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Bell
Aircraft Model 206-B
Aircraft Series Identifier 206-B
Aircraft Serial Number 4039
Certified Max Gross Weight 3200
Aircraft Category Helicopter
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 5
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Sep 9 1998 12:00AM
Airframe hours since last inspection 69
Airframe Hours 3169
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name HELICOPTER INC
Aircraft Owner Street Address 14 OMEGA DRIVE
Aircraft Owner City CAHOKIA
Aircraft Owner State IL
Aircraft Owner Country
Aircraft Owner Zipcode 62206
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
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) Aerial Observation
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code 43KY
Departure City
Departure State KY
Departure Country
Departure Time 1700
Departure Time Zone EST
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code
Destination City
Destination State
Destination Country
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --