Individually Owned: 150,657
Corporate Owned: 137,281
Dallas-Ft. Worth Intl Airport
Aircraft Accident/Incident Report
Dfw Airport, Texas 75261
Thursday, March 27, 1997 8:45 CST
NTSB Narrative Summary Released at Completion of Accident
During the landing approach, with the flaps extended to 15 degrees and the spoilers deployed, an 18-foot section of the right outboard flap separated from the trailing edge of the right wing. After making a flyby of the tower to allow controllers to view the extent of the damage, the flightcrew landed the airplane without further incident. The flap separation resulted from fatigue cracking of the four aft bolts fastening the flap to the inboard flap carriage support beam. The relief shoulders on three of the bolts exhibited thread contact marks which indicated that the attachment nuts were inserted all the way down to the relief shoulders. Either the bolt grip lengths were longer than necessary for this installation, or not enough shims were installed under the heads of the bolts or attachment nuts. Under these circumstances, the bolts most likely did not receive sufficient preload in tension, since the nuts probably bottomed onto the relief shoulders before the preload could be produced. Maintenance records indicated that the flap had not been removed from the wing since manufacture of the airplane in 1982 and had accumulated 45,577 flight hours and 22,155 flight cycles.
NTSB Probable Cause Narrative
The manufacturer's improper installation of the flap, which resulted in fatigue cracking of the flap attach bolts and separation of the flap.
Event Information
| Type of Event | Incident |
| Event Date | 3/27/1997 |
| Event Day of the Week | Thursday |
| Time of Event | 845 |
| Event Time Zone | Central Standard Time |
| Event City | DFW AIRPORT |
| Event State | TEXAS |
| Event Country | -- |
| Zipcode of the event site | 75261 |
| Event Date Year | 1997 |
| Event Date Month | 3 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | |
| Event Location Longitude | |
| Event Location Airport | DALLAS-FT. WORTH INTL |
| Event Location Nearest Airport ID | DFW |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 10 |
| Degrees magnetic from airport | 45 |
| Airport Elevation | 603 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 853 Central Standard Time |
| Direction of event from weather observation facility (degrees) | 225 |
| Weather Observation Facility ID | DFW |
| Elevation of weather observation facility | 603 |
| Distance of event from weather observation facility (units?) | 9 |
| Time Zone of the weather observation | CST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 8500 |
| Lowest Non-Ceiling Height | 0 |
| Sky/Lowest/Cloud Conditions | Unknown |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 14 |
| Dew Point at event time (in degress fahrenheit) | 8 |
| Wind Direction (degrees magnetic) | 170 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 6 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 30 |
| Density Altitude (feet) | -- |
| 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 | 198 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 5017 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Mar 27 1997 12:00AM |
| NTSB Notification Time | 949 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 8 2000 12:09PM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N105DA |
| NTSB Number | FTW97IA144 |
| 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 | 767-232 |
| Aircraft Series Identifier | 767-232 |
| Aircraft Serial Number | 22217 |
| Certified Max Gross Weight | 335000 |
| 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 | 207 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Feb 15 1997 12:00AM |
| Airframe hours since last inspection | 283 |
| Airframe Hours | 45577 |
| ELT Installed | Unknown |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | DELTA AIR LINES, INC. |
| Aircraft Owner Street Address | 1030 DELTA BLVD. |
| Aircraft Owner City | ATLANTA |
| Aircraft Owner State | GA |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 30320 |
| Operator is an individual? | -- |
| 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 | 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 | No |
| Departure Airport Code | MCO |
| Departure City | ORLANDO |
| Departure State | FL |
| Departure Country | |
| Departure Time | 0 |
| Departure Time Zone | |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | DFW |
| Destination City | |
| Destination State | |
| Destination Country | |
| Specific Phase of Flight | Approach |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Dec 20 2002 12:42PM |
| User who most recently changed record | dbo |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | 17R |
| Runway Length | 13400 |
| Runway Width | 200 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |