Kalispell Regional Hospital Airport
Aircraft Accident/Incident Report

Kalispell, Montana 59901
Thursday, November 2, 2006 20:55 MST

NTSB Narrative Summary Released at Completion of Accident

While conducting EMS operations the helicopter sustained substantial damage after a loss of engine power, autorotation, and forced landing. The pilot reported hearing a loud bang, followed by the engine spooling down. The helicopter collided with a chain link fence during the forced landing sequence. Postaccident inspection of the engine revealed an uncontained second stage turbine wheel burst (on-speed) as a result of oil starvation and subsequent bearing failure. During the onsite examination, fresh oil residue was noted along the right side of the helicopter's fuselage, tail boom assembly and leading edges of the tail rotor blades. Oil wetting and staining was also observed on the concrete hangar apron, and a trail of fresh oil extended from apron to the helipad where the helicopter departed. Additionally, onsite investigators noted that the oil pressure transducer line coupling B-nut (near the foreword bulkhead) was found two flats loose, and four complete rotations from complete separation. Evidence of oil loss, sooting and localized fire damage was observed in the area of the fitting union. The accident flight was the helicopter's first flight following the completion of a maintenance action item in the general area of the aforementioned fitting. Following the maintenance action, an engine run (ground) and post run inspection was completed by a line pilot. No discrepancies were noted and the helicopter was returned to service. The mechanic who performed the maintenance action was not present during the post run inspection.

NTSB Probable Cause Narrative

On-speed failure of the second stage turbine wheel as the result of engine oil starvation. The lack of maintenance oversight was a contributing factor.

Event Information

Type of Event Accident
Event Date 11/2/2006
Event Day of the Week Thursday
Time of Event 2055
Event Time Zone Mountain Standard Time
Event City Kalispell
Event State MONTANA
Event Country --
Zipcode of the event site 59901
Event Date Year 2006
Event Date Month 11
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 481282N
Event Location Longitude 1141938W
Event Location Airport KALISPELL REGIONAL HOSPITAL
Event Location Nearest Airport ID MT28
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation 2970
Weather Briefing Completeness --
Investigator's weather source Weather Observation Facility
Time of the weather observation 2055 Mountain Standard Time
Direction of event from weather observation facility (degrees) 20
Weather Observation Facility ID KGPI
Elevation of weather observation facility 2977
Distance of event from weather observation facility (units?) 6
Time Zone of the weather observation MST
Lighting Conditions Night/Dark
Lowest Ceiling Height 1700
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions --
Sky Condition for Lowest Ceiling Overcast
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 2
Air Temperature at event time (in degrees celsius) -2
Dew Point at event time (in degress fahrenheit) -3
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) 0
Wind Velocity Indicator --
Wind Gust Indicator Unknown
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 29.95
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 3
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 22487
NTSB Notification Source FAA-ROC
NTSB Notification Date Nov 2 2006 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Nov 29 2007 8:02AM
User who most recently changed record NTSB\johb
Basic weather conditions Visual Meteorological Cond
FAA District Office Helena, Montana

Aircraft Involved

Aircraft #1

Aircraft Registration Number N407KH
NTSB Number SEA07FA014
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 In-flight
Aircraft Explosion None
Aircraft Manufacturer's Full Name Bell
Aircraft Model 407
Aircraft Series Identifier --
Aircraft Serial Number 53395
Certified Max Gross Weight 5250
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 5
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection AAIP
Date of Last Inspection Sep 1 2006 12:00AM
Airframe hours since last inspection 68
Airframe Hours 3138
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Yes
ELT Type --
Aircraft Owner Name Kalispell Regional Medical Center
Aircraft Owner Street Address 325 Claremont Street
Aircraft Owner City Kalispell
Aircraft Owner State MT
Aircraft Owner Country USA
Aircraft Owner Zipcode 59901
Operator is an individual? No
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 --
Other Operator of large aircraft? --
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) Positioning
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code MT28
Departure City KALISPELL
Departure State MT
Departure Country USA
Departure Time 2051
Departure Time Zone HST
Destination Same as Local Flt crash at destination city
Destination Airport Code --
Destination City Kalispell
Destination State MT
Destination Country USA
Specific Phase of Flight Emergency landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Oct 11 2007 4:25PM
User who most recently changed record STAM
Since inspection or accident Last Inspection
Event Location Runway Number and Location H
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight Yes
Medical Flight Medical Emergency