Aircraft Incident/Accident Report
San Francisco Intl Airport

San Francisco, California 94128
Monday, March 13, 2000 20:06 PST

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NTSB Narrative Summary Released at Completion of Accident
The airplane landed with the right main landing gear partially extended. This was the second leg of the day in the airplane for this crew; the second officer (SO) completed walk around inspections prior to both flights and noted no discrepancies. The captain was hand flying the airplane in the initial takeoff climb, and selected landing gear up passing through 300 to 500 feet above ground level (agl). The red "doors" light illuminated on the front panel and the amber right main gear door light illuminated on the second officer's panel. All attempts to lower the right main gear were unsuccessful, so the captain elected to return to the airport and land with the right main gear extended about 15 degrees. Inspection of the right main landing gear revealed that the safety bar bent down about 20 degrees at the leading edge and 15 degrees at its midpoint. The safety bar's inboard flanges buckled just below the reinforced area. The inner gear door drive rod bent aft about 15 degrees at the upper attachment fitting, and the tube buckled and separated below the four attachment nuts. The outboard section of the clamshell gear door sustained mechanical damage. Examination of the airplane revealed that the door rods were not loose, and all were in good condition. A general inspection of the wheel well revealed no other damage. There was no abnormal wear or movement marks on the up-lock hook, and the hook was properly adjusted. The actuator adjustor plate was properly installed. Delta maintenance technicians installed new clamshell door halves and a new drive rod. They serviced the strut, isolated the right main clamshell gear door, and cycled the gear. Then they cycled the right main wheel with the door. Finally, they cycled all of the landing gear together. All wheels and doors cycled in proper sequence. Metallurgical examination discovered no cracks in the safety plate. There were no fatigue crack arrest marks or corrosion in the fracture faces on the drive rod; it fractured as a result of overstress. A black coating that felt greasy covered the interior side of the outer clamshell door. There was a rectangular scuffmark in the center of the black area, which had its long axis parallel to the longitudinal axis of the airplane. The black coating appeared pushed into a slight ridge along the outer edge of the scuffmark. A small piece of rubber was under a rivet in the middle of the scuffmark. After placing the tire and gear door together to match their positions when the airplane came to rest, the tire did not touch the scuffmark. Fourier Transform Infrared Spectroscopy (FTIR) examination of the small piece of rubber and samples from the tire and a chock determined that they were all hydrocarbon compounds, but could not distinguish between the samples. Whether the scuffmark and rubber piece came from runway debris or another rubber object could not be determined.
NTSB Probable Cause Narrative
failure of the right main landing gear to fully extend for undetermined reasons.
Event Information
Type of EventIncident 
Event Date3/13/2000 
Event Day of the WeekMonday 
Time of Event2006 
Event Time ZonePacific Standard Time 
Event CitySAN FRANCISCO 
Event StateCALIFORNIA 
Event Country-- 
Zipcode of the event site94128 
Event Date Year2000 
Event Date Month
MidAir Collision IndicatorNo 
On Ground Collision occurred ?No 
Event Location Latitude373713N 
Event Location Longitude1222248W 
Event Location AirportSAN FRANCISCO INTL 
Event Location Nearest Airport IDSFO 
Indicates whether the acc/inc occurred off or on an airportOn Airport 
Distance from airport in statute miles-- 
Degrees magnetic from airport-- 
Airport Elevation13 
Weather Briefing CompletenessUnknown 
Investigator's weather sourceWeather Observation Facility 
Time of the weather observation1956 Pacific Standard Time 
Direction of event from weather observation facility (degrees)
Weather Observation Facility IDSFO 
Elevation of weather observation facility
Distance of event from weather observation facility (units?)
Time Zone of the weather observationPST 
Lighting ConditionsNight/Dark 
Lowest Ceiling Height-- 
Lowest Non-Ceiling Height800 
Sky/Lowest/Cloud ConditionsScattered 
Sky Condition for Lowest CeilingNone 
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)11 
Wind Direction (degrees magnetic)260 
Variable Wind IndicatorWind direction could be determined 
Wind Speed (knots)18 
Wind Velocity Indicator -- 
Wind Gust IndicatorNot Gusting 
Wind Gust (knots) -- 
Altimeter Setting at event time (in. Hg) 30.18 
Density Altitude (feet)-- 
Intensity of Precipitation-- 
METAR weather report -- 
Event Highest InjuryNone 
On Ground, Fatal Injuries
On Ground, Minor Injuries
On Ground, Serious Injuries
Injury Total Fatal-- 
Injury Total Minor-- 
Injury Total None77 
Injury Total Serious-- 
Injury Total All-- 
Investigating AgencyNTSB 
NTSB Docket Number (internal use)20578 
NTSB Notification Source-- 
NTSB Notification DateMar 13 2000 12:00AM 
NTSB Notification Time2015 
Fiche Number and/or location -used to find docket informationDMS 
Date of most recent change to recordOct 31 2006 8:45AM 
User who most recently changed recordNTSB\JOHB  
Basic weather conditionsVisual Meteorological Cond 
FAA District Office-- 
Aircraft Involved
Aircraft #1
Aircraft Registration NumberN516DA 
NTSB NumberLAX00IA127 
Missing Aircraft Indicator
Federal Aviation Reg. PartPart 121: Air Carrier 
Type of Flight Plan filedIFR 
Flight plan Was Activated?Yes 
DamageMinor 
Aircraft FireNone 
Aircraft ExplosionNone 
Aircraft Manufacturer's Full NameBoeing 
Aircraft Model727-232 
Aircraft Series Identifier727-232 
Aircraft Serial Number21432 
Certified Max Gross Weight184200 
Aircraft CategoryAirplane 
Aircraft Registration ClassUnknown 
Aircraft is a homebuilt?No 
Flight Crew Seats-- 
Cabin Crew Seats-- 
Passenger Seats-- 
Total number of seats on the aircraft156 
Number of Engines
Fixed gear or retractable gearRetractable 
Aircraft, Type of Last InspectionContinuous Airworthiness 
Date of Last InspectionMar 1 2000 12:00AM 
Airframe hours since last inspection42.1 
Airframe Hours63246.5 
ELT Installed-- 
ELT Activated-- 
ELT Aided Location of Event Site-- 
ELT Type-- 
Aircraft Owner NameWILMINGTON TRUST CO. TRUSTEE 
Aircraft Owner Street AddressRODNEY SQ ATTN EQUIP LEASING 
Aircraft Owner CityWILMINGTON 
Aircraft Owner StateDE 
Aircraft Owner CountryUSA  
Aircraft Owner Zipcode19890 
Operator is an individual?No 
Operator NameDELTA AIRLINES, INC. 
Operator Same as Owner?No 
Operator Is Doing Business As-- 
Operator Address Same as Owner?No 
Operator Street AddressPO BOX 20706 
Operator CityATLANTA 
Operator StateGA 
Operator CountryUSA  
Operator Zip code30320 
Operator CodeDALA 
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 notScheduled 
Indicates Domestic or International FlightDomestic 
Operator carrying Pax/Cargo/MailPassenger Only 
Type of Flying (Per_Bus / Primary)Unknown 
Second Pilot on BoardYes 
Departure Point Same as EventYes 
Departure Airport CodeSFO  
Departure CitySAN FRANCISCO 
Departure StateCA 
Departure CountryUSA 
Departure Time1835 
Departure Time ZonePST 
Destination Same as Local Flt-- 
Destination Airport CodeSLC  
Destination CitySALT LAKE CITY 
Destination StateUT 
Destination CountryUSA 
Specific Phase of FlightTakeoff 
Report sent to ICAO?-- 
Evacuation occurred-- 
Date of most recent change to recordAug 25 2006 3:33PM 
User who most recently changed recordCOOS  
Since inspection or accident-- 
Event Location Runway Number and Location28R 
Runway Length11870 
Runway Width200 
Sight Seeing flightNo 
Air Medical FlightNo 
Medical Flight--