Individually Owned: 150,657
Corporate Owned: 137,281
Minneapolis-St Paul Intl/Wold- Airport
Aircraft Accident/Incident Report
Minneapolis, Minnesota 55450
Sunday, September 22, 2002 18:52 CDT
NTSB Narrative Summary Released at Completion of Accident
The airplane was damaged when the right main landing gear failed and collapsed during taxi for takeoff. A dark spot observed on the fracture surface showed a region with intergranular fracture features at the origin of the fracture with other areas of fatigue and intergranular fracture. Outside of the dark spot, the fracture features were consistent with overstress. Examination of the fractured landing gear revealed that small subsurface inclusions were present in the area near the fracture origin. Dissolved hydrogen content testing revealed hydrogen content ranging from 1 to 5 ppm. Residual stress tests show that the cylinder had compressive stress layers at the outer surface consistent with shot peening. The stress profiles showed maximum compressive stresses of 200 to 250 ksi transitioning to residual tensile stresses between 0.01 and 0.02 inch below the surface.
NTSB Probable Cause Narrative
The fatigue failure of the main landing gear strut due to inclusions in the material, residual stresses, and dissolved hydrogen content.
Event Information
| Type of Event | Accident |
| Event Date | 9/22/2002 |
| Event Day of the Week | Sunday |
| Time of Event | 1852 |
| Event Time Zone | Central Daylight Time |
| Event City | Minneapolis |
| Event State | MINNESOTA |
| Event Country | -- |
| Zipcode of the event site | 55450 |
| Event Date Year | 2002 |
| Event Date Month | 9 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 445250N |
| Event Location Longitude | 0931301W |
| Event Location Airport | MINNEAPOLIS-ST PAUL INTL/WOLD- |
| Event Location Nearest Airport ID | MSP |
| 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 | 841 |
| Weather Briefing Completeness | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1853 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | 0 |
| Weather Observation Facility ID | KMSP |
| Elevation of weather observation facility | 841 |
| Distance of event from weather observation facility (units?) | 0 |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 20000 |
| Lowest Non-Ceiling Height | 6000 |
| Sky/Lowest/Cloud Conditions | Few |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 12 |
| Dew Point at event time (in degress fahrenheit) | 2 |
| Wind Direction (degrees magnetic) | 300 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 5 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.1 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | METAR KMSP 222353Z 30005KT 10SM FEW060 BKN200 12/0 |
| 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 | 85 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 15063 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Sep 22 2002 12:00AM |
| NTSB Notification Time | 1930 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Mar 30 2004 8:14AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Minneapolis, Minnesota - CMO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N941N |
| NTSB Number | CHI02FA289 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | McDonnell Douglas |
| Aircraft Model | DC-9-32 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 47450 |
| Certified Max Gross Weight | 109800 |
| Aircraft Category | Airplane |
| 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 | 85 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | AAIP |
| Date of Last Inspection | Sep 10 2002 12:00AM |
| Airframe hours since last inspection | 105 |
| Airframe Hours | 62452 |
| ELT Installed | No |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | NORTHWEST AIRLINES INC |
| Aircraft Owner Street Address | 5101 Northwest Drive C7-8960 |
| Aircraft Owner City | St. Paul |
| Aircraft Owner State | MN |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 55111 |
| 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 | NWAA |
| 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 | Scheduled |
| Indicates Domestic or International Flight | Domestic |
| Operator carrying Pax/Cargo/Mail | Passenger Only |
| Type of Flying (Per_Bus / Primary) | -- |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | Yes |
| Departure Airport Code | MSP |
| Departure City | Minneapolis |
| Departure State | MN |
| Departure Country | USA |
| Departure Time | 1852 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | CLT |
| Destination City | CHARLOTTE |
| Destination State | NC |
| Destination Country | USA |
| Specific Phase of Flight | Taxi - to takeoff |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Feb 17 2004 9:38AM |
| User who most recently changed record | SULP |
| 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 | -- |