Individually Owned: 151,845
Corporate Owned: 143,699
Miami International Airport
Aircraft Accident/Incident Report
Miami, Florida 33132
Sunday, August 24, 2003 11:10 EDT
NTSB Narrative Summary Released at Completion of Accident
The first officer stated that during preflight examination of the airplane he didn't see anything wrong with the aircraft and it was deemed suitable for flight. During taxi, the airplane suddenly dipped left and skidded to a stop. The flightcrew assessed a possible tire blowout and after contacting ground control the aircraft behind them confirmed it was the left outboard main tire and that it was smoking. Airport emergency authorities responded and noted the left main landing gear had failed. The authorities observed no smoke or fire. Maintenance personnel confirmed that the bogie on the left main gear had failed. The left main landing gear truck beam had fractured in two pieces between the aft axle and the truck pivot pin. There was no truck beam shield present with the wreckage although the attach straps were present. The fracture occurred about 14 inches forward of the aft axle centerline. Metallurgical analysis revealed the fracture of the truck beam was the result of stress corrosion cracking (SCC). The SCC was precipitated by damage to the protective finishes on the lower surface of the beam. The material of the beam is very susceptible to SCC at the high strengths specified. It is vitally important to maintain the protective finishes and prevent exposure of the base material to atmospheric conditions when loaded. According to operator, the landing gear was delivered new with the airplane on July 29, 1996 and had accumulated 7,517 cycles since new. There was no truck beam shield present with the wreckage although the attach straps were present. The Boeing 757 configuration deviation list (CDL), which was current at the time of the incident, lists items that can be missing for flight. The main landing gear truck beam shields may be missing for flight. There was no requirement to inspect the landing gear for damage prior to dispatch with a truck beam shield missing. Maintenance personnel had not identified the missing truck beam shield on the left main landing gear of the airplane and the shield was not on the current list of missing items under the CDL.
NTSB Probable Cause Narrative
The failure of maintenance personnel from the aircraft operator to identify a missing left main landing gear truck beam shield and damage to the left main landing gear truck beam which resulted in the fracture of the truck beam as a result of stress corrosion cracking.
Event Information
| Type of Event | Incident |
| Event Date | 8/24/2003 |
| Event Day of the Week | Sunday |
| Time of Event | 1110 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Miami |
| Event State | FLORIDA |
| Event Country | -- |
| Zipcode of the event site | 33132 |
| Event Date Year | 2003 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 254735N |
| Event Location Longitude | 0801726W |
| Event Location Airport | Miami International |
| Event Location Nearest Airport ID | MIA |
| 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 | 8 |
| Weather Briefing Completeness | Full |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1153 Eastern Standard Time |
| Direction of event from weather observation facility (degrees) | 270 |
| Weather Observation Facility ID | KMIA |
| Elevation of weather observation facility | 8 |
| Distance of event from weather observation facility (units?) | 1 |
| Time Zone of the weather observation | EST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 2500 |
| Sky/Lowest/Cloud Conditions | Scattered |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 32 |
| Dew Point at event time (in degress fahrenheit) | 22 |
| Wind Direction (degrees magnetic) | 0 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 0 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.04 |
| Density Altitude (feet) | 1200 |
| 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 | 169 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 17030 |
| NTSB Notification Source | Metro Dade Airport Auth. |
| NTSB Notification Date | Aug 24 2003 12:00AM |
| NTSB Notification Time | 1120 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Dec 28 2004 12:45PM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Miami FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N609AA |
| NTSB Number | MIA03IA168 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | No |
| Damage | Minor |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Boeing |
| Aircraft Model | 757-223 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 27447 |
| Certified Max Gross Weight | 251000 |
| 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 | 187 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Aug 24 2003 12:00AM |
| Airframe hours since last inspection | 1 |
| Airframe Hours | 25608 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | AMERICAN AIRLINES INC |
| Aircraft Owner Street Address | PO Box 619616 MD 5662 |
| Aircraft Owner City | DFW Airport |
| Aircraft Owner State | TX |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 75261 |
| 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 | AALA |
| 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 | MIA |
| Departure City | Miami |
| Departure State | FL |
| Departure Country | USA |
| Departure Time | 1110 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | ORD |
| Destination City | CHICAGO |
| Destination State | IL |
| Destination Country | USA |
| Specific Phase of Flight | Taxi - to takeoff |
| Report sent to ICAO? | Yes |
| Evacuation occurred | No |
| Date of most recent change to record | Nov 15 2004 1:42PM |
| User who most recently changed record | KENJ |
| 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 | -- |