Aircraft Accident/Incident Report

Bogota Colombia
Thursday, March 26, 2009 6:15 UTC

NTSB Narrative Summary Released at Completion of Accident

The airplane experienced an uncontained No. 2 engine failure during climb out after takeoff, and an uneventful landing was accomplished. A post-incident airplane inspection found that the No. 2 engine low pressure turbine (LPT) case had separated circumferentially in plane with the LPT stage 3 (S3) turbine and that all components aft of the separation were liberated. The engine's LPT S3 disk front spacer arm was fractured circumferentially at the spacer to disk rim fillet. Metallurgical examination of the fracture surfaces revealed high cycle, high-amplitude fatigue (HAF) cracks initiating from sites around 90 percent of the forward spacer arm inner diameter. Inspection of the high pressure turbine (HPT) found that one stage 1 (S1) blade was missing approximately 85 percent of its airfoil material. The investigation found that the HPT blade damage resulted in synchronous vibration forces that interacted with the engine LPT rotor system through a common bearing support and excited a bladed-disk mode response in the LPT S3 disk. The resonant amplitude of the alternating stress experienced by the disk resulted in bending loads that exceeded the material endurance limit and caused high cycle/high amplitude fatigue cracks to initiate along the LPT S3 disk forward spacer arm rim diameter. Once initiated, the cracks propagated rapidly through the spacer arm thickness and the individual cracks joined to form a single circumferential crack, resulting in the separation of the disk at the forward spacer arm. The freed aft portion of the LPT rotor accelerated and penetrated the engine case, releasing high-energy debris as disk fragments and all of the engine components aft of the LPT S3 nozzles were liberated.

NTSB Probable Cause Narrative

Failure of the low pressure turbine stage 3 disk due to a design that is vulnerable to high pressure turbine unbalance-induced synchronous vibration that cannot be detected in flight, and the subsequent uncontained engine failure.

Event Information

Type of Event Incident
Event Date 3/26/2009
Event Day of the Week Thursday
Time of Event 615
Event Time Zone Coordinated Universal Time? Same as GMT
Event City Bogota
Event State --
Event Country COLOMBIA
Zipcode of the event site --
Event Date Year 2009
Event Date Month 3
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 --
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness --
Investigator's weather source Unknown
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 --
Lowest Ceiling Height --
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions --
Sky Condition for Lowest Ceiling --
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) --
Air Temperature at event time (in degrees celsius) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) --
Wind Velocity Indicator --
Wind Gust Indicator --
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 4
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 30856
NTSB Notification Source operator
NTSB Notification Date --
NTSB Notification Time --
Fiche Number and/or location -used to find docket information --
Date of most recent change to record Dec 17 2012 2:23PM
User who most recently changed record horc
Basic weather conditions --
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N526MD
NTSB Number ENG09IA004
Missing Aircraft Indicator --
Federal Aviation Reg. Part Unknown
Type of Flight Plan filed Unknown
Flight plan Was Activated? --
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name MCDONNELL-DOUGLAS
Aircraft Model DC-10-30
Aircraft Series Identifier --
Aircraft Serial Number 46998
Certified Max Gross Weight --
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 345
Number of Engines 3
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection --
Date of Last Inspection --
Airframe hours since last inspection --
Airframe Hours --
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name MIAMI LEASING INC
Aircraft Owner Street Address 1701 NW 63RD AVE BLDG 712
Aircraft Owner City MIAMI
Aircraft Owner State FL
Aircraft Owner Country USA
Aircraft Owner Zipcode 33126-7300
Operator is an individual? No
Operator Name Arrow Cargo
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address --
Operator City --
Operator State --
Operator Country USA
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 --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Scheduled
Indicates Domestic or International Flight International
Operator carrying Pax/Cargo/Mail Cargo
Type of Flying (Per_Bus / Primary) --
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code --
Departure City --
Departure State --
Departure Country USA
Departure Time --
Departure Time Zone --
Destination Same as Local Flt --
Destination Airport Code --
Destination City --
Destination State --
Destination Country USA
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Dec 17 2012 1:29PM
User who most recently changed record horc
Since inspection or accident --
Event Location Runway Number and Location --
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --