Stapelton Int'l Airport
Aircraft Accident/Incident Report

Denver, Colorado 80207
Wednesday, May 24, 1989 8:05 MDT

NTSB Narrative Summary Released at Completion of Accident

THE LEFT MAIN LANDING GEAR COLLAPSED AS THE AIRCRAFT WAS PULLED FORWARD SLIGHTLY TO BRING THE NOSEWHEEL OFF THE CHOCKS PRIOR TO PUSHBACK. INSPECTION DISCLOSED A FRACTURE OF THE FORWARD TRUNNION BEARING SUPPORT FITTING (P/N 65-16206-11) AND HEAVY SURFACE CORROSION. MICROSCOPIC EXAMINATION DISCLOSED EXTENSIVE INTERGRANULAR STRESS CORROSION, AND A CRACK THAT HAD DEVELOPED 0.1 INCHES INBOARD FROM THE FORWARD EDGE OF THE BORE, WHICH HAD PROPAGATED APPROXIMATELY 2.1 INCHES AFT INTO THE BORE SURFACE. THE FINAL FRACTURE RESULTED FROM DUCTILE SEPARATION.

NTSB Probable Cause Narrative

FAILURE OF THE LEFT MAIN LANDING GEAR FORWARD TRUNNION BEARING SUPPORT FITTING DUE TO A CRACK INITIATING AT THE FORWARD EDGE OF THE BORE AND PROPAGATING BY INTERGRANULAR STRESS CORROSION INTO THE BORE SURFACE THAT RESULTED IN AN EVENTUAL DUCTILE FRACTURE.

Event Information

Type of Event Incident
Event Date 5/24/1989
Event Day of the Week Wednesday
Time of Event 805
Event Time Zone Mountain Daylight Time
Event City DENVER
Event State COLORADO
Event Country --
Zipcode of the event site 80207
Event Date Year 1989
Event Date Month 5
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport STAPELTON INT'L
Event Location Nearest Airport ID KDEN
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles 0
Degrees magnetic from airport 0
Airport Elevation 5333
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 824 Mountain Daylight Time
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID DEN
Elevation of weather observation facility 5333
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation MDT
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 20000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 60
Air Temperature at event time (in degrees celsius) 20
Dew Point at event time (in degress fahrenheit) -1
Wind Direction (degrees magnetic) 90
Variable Wind Indicator Unknown
Wind Speed (knots) 8
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) 7362
Intensity of Precipitation Unknown
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 121
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 5011
NTSB Notification Source --
NTSB Notification Date May 24 1989 12:00AM
NTSB Notification Time 930
Fiche Number and/or location -used to find docket information 40096
Date of most recent change to record Dec 13 2000 12:40PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N296WA
NTSB Number DEN89IA124
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 121: Air Carrier
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name BOEING
Aircraft Model 727-247
Aircraft Series Identifier 727-247
Aircraft Serial Number 22533
Certified Max Gross Weight 190500
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 157
Number of Engines 3
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Apr 27 1989 12:00AM
Airframe hours since last inspection 217
Airframe Hours 25391
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name FIRST SECURITY BANK OF UTAH
Aircraft Owner Street Address 79 SOUTH MAIN STREET
Aircraft Owner City SALT LAKE CITY
Aircraft Owner State UT
Aircraft Owner Country
Aircraft Owner Zipcode 84111
Operator is an individual? --
Operator Name DELTA AIR LINES
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address HARTSFIELD INT'L AIRPORT
Operator City ATLANTA
Operator State GA
Operator Country
Operator Zip code 30320
Operator Code DALA
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
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) Unknown
Second Pilot on Board Yes
Departure Point Same as Event Yes
Departure Airport Code DEN
Departure City
Departure State
Departure Country
Departure Time 0
Departure Time Zone
Destination Same as Local Flt --
Destination Airport Code ATL
Destination City ATLANTA
Destination State GA
Destination Country
Specific Phase of Flight Taxi
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:30AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --