Delta Air Lines Boeing 727-247 incident
Boeing 727-247 · Incident: main gear collapsed during pushback
From Denver International Airport (DEN) to Hartsfield Jackson Atlanta International Airport (ATL)
Event
- NTSB case
- DEN89IA124
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Incident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Boeing 727-247
- Aircraft type
- Boeing 727
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N296WA
- Operator
- Delta Air Lines
- Onboard fatalities
- Unknown
- Route
- From Denver International Airport (DEN)To Hartsfield Jackson Atlanta International Airport (ATL), Atlanta, GA
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air Carrier
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Pushback/towing
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Main gear collapsed
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Cause areas
- Landing gear, main gear attachment › Failure, total
- Landing gear, main gear attachment › Fractured
- Landing gear, main gear attachment › Stress corrosion
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
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.
Probable cause
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.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN89IA124
- Event ID
- 20001213X28288
- Case number
- DEN89IA124
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 9c36727dc4f05b08c03853ba6d04a42d653e9955176be8b3b632ca0c731976df; retrieved 2026-09-18T19:11:29.407Z.