San Carlos Apache Airport
Aircraft Accident/Incident Report

Globe, Arizona 85501
Friday, July 22, 2005 8:30 MST

NTSB Narrative Summary Released at Completion of Accident

The airplane impacted a road and scrub brush during a forced landing, which was preceded by a total loss of engine power. According to the pilot, he heard a loud "thunk" during takeoff climb and noted a loss of engine power. He manipulated the power lever from the full forward position to the full aft position ("stop-to-stop") and noted he had no power. Post-accident examination of the Pratt & Whitney Canada PT6A -114A engine revealed that the compressor turbine (CT) vane's outer rim liberated a section of metal that damaged the turbine blades downstream. The area of liberated material from the CT vane outer rim was examined by the manufacturer's metallurgists. The fracture surface of the outer rim showed evidence of fatigue with signs of oxidation in some areas indicating the crack had been in existence for some time. The liberated material impact damaged the CT blades and resulted in a loss of power. Review of the operator's records revealed that the engine was approved for an extension beyond the normally recommended 3,600-hour overhaul period, to 5,100 hours. The engine had accumulated 4,461.3 hours at the time of the accident. In addition, the turbine section (hot section) had a recommended overhaul period of 1,800 hours; however, the operator instead elected to utilize an engine trend monitoring program in accordance with a manufacturer issued service bulletin. Many errors were noted with the operator's manually recorded data utilized for the trend monitoring. However, it is not likely that the engine trend data, even had it been correctly recorded and monitored, would have depicted the fatigue cracking in the CT vane outer rim. As a result, the manufacturer issued a service information letter (SIL) PT6A-116 in January 27, 2003 (following a similar investigation), which reminded operators to conduct borescope inspections of the CT vane during routine fuel nozzle maintenance, as the manufacturer's maintenance manual recommended. Review of the maintenance record entries for the accident engine revealed no evidence that a borescope inspection had been conducted in conjunction with the fuel nozzle checks.

NTSB Probable Cause Narrative

The fatigue failure of the compressor turbine stator vane, the liberation of vane material into the compressor turbine, and the total loss of engine power. Also causal was the operator's failure to inspect the compressor turbine vane during fuel nozzle checks.

Event Information

Type of Event Accident
Event Date 7/22/2005
Event Day of the Week Friday
Time of Event 830
Event Time Zone Mountain Standard Time
Event City Globe
Event State ARIZONA
Event Country --
Zipcode of the event site 85501
Event Date Year 2005
Event Date Month 7
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 332101N
Event Location Longitude 1103818W
Event Location Airport San Carlos Apache Airport
Event Location Nearest Airport ID P13
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 0.5
Degrees magnetic from airport --
Airport Elevation 3261
Weather Briefing Completeness --
Investigator's weather source Pilot
Time of the weather observation
Direction of event from weather observation facility (degrees) --
Weather Observation Facility ID --
Elevation of weather observation facility --
Distance of event from weather observation facility (units?) --
Time Zone of the weather observation --
Lighting Conditions Day
Lowest Ceiling Height 25000
Lowest Non-Ceiling Height 25000
Sky/Lowest/Cloud Conditions Thin Overcast
Sky Condition for Lowest Ceiling Overcast
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 60
Air Temperature at event time (in degrees celsius) 27
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) --
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor 1
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 21541
NTSB Notification Source FAA
NTSB Notification Date Jul 22 2005 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record May 29 2007 12:24PM
User who most recently changed record NTSB\lema
Basic weather conditions Visual Meteorological Cond
FAA District Office WP-SDL-FSDO

Aircraft Involved

Aircraft #1

Aircraft Registration Number N717BT
NTSB Number LAX05LA244
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 135: Air Taxi & Commuter
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Cessna
Aircraft Model 208B
Aircraft Series Identifier --
Aircraft Serial Number 208B0863
Certified Max Gross Weight 8750
Aircraft Category Airplane
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 2
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Jul 1 2005 12:00AM
Airframe hours since last inspection 4372.8
Airframe Hours 4461.4
ELT Installed Yes
ELT Activated --
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Tarene Leasing LLC
Aircraft Owner Street Address 1723 McCollum Parkway #200
Aircraft Owner City Kennesaw
Aircraft Owner State GA
Aircraft Owner Country USA
Aircraft Owner Zipcode 30152
Operator is an individual? No
Operator Name Baltimore Air Transport
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 7509 General Aviation Blvd.
Operator City Ft. Meade
Operator State MD
Operator Country USA
Operator Zip code 20755
Operator Code B7LA
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 Non-scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Cargo
Type of Flying (Per_Bus / Primary) --
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code P13
Departure City Globe
Departure State AZ
Departure Country USA
Departure Time --
Departure Time Zone MST
Destination Same as Local Flt --
Destination Airport Code SAD
Destination City Safford
Destination State AZ
Destination Country USA
Specific Phase of Flight Takeoff - initial climb
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record May 17 2007 8:02PM
User who most recently changed record STAM
Since inspection or accident Time of Accident
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --