Southern Air Transport McDonnell Douglas DC-8-71 incident
McDonnell Douglas DC-8-71 · Incident: gear not retracted en route
Event
- NTSB case
- CHI93IA035
- 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
McDonnell Douglas DC-8-71
- Aircraft type
- McDonnell Douglas DC-8
- 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
- N870SJ
- Operator
- Southern Air Transport
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- 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
- En route · climb to cruise
- 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
- Gear not retracted
- 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
- Other maintenance personnel › Maintenance, major repair, improper
Approximate · Estimated position: the centre of Chicago, IL, the place the record names. Not the accident site.
NTSB narrative
THE CREW OF THE MCDONNELL-DOUGLAS DC-8 CARGO AIRPLANE RETRACTED THE LANDING GEAR DURING ITS CLIMB TO CRUISE ALTITUDE. THE CREW ADVISED AIR TRAFFIC CONTROL THAT THE LANDING GEAR HAD NOT RETRACTED PROPERLY. DURING AN ATTEMPT TO ENSURE THE LANDING GEAR WAS IN THE DOWN AND LOCKED POSITION THE CREW HEARD A LOUD BANG. COINCIDENTAL WITH THE AIRCREW'S ACTIONS, A PERSON RESIDING IN A SINGLE FAMILY HOME REPORTED THAT A METAL OBJECT HAD PENETRATED HER HOME'S ROOF AND IMBEDDED ITSELF IN THE FLOOR. THE AIRPLANE RETURNED TO LAND WITHOUT FURTHER INCIDENT. AN ON-SCENE INVESTIGATION REVEALED THE RIGHT MAIN LANDING GEAR RETRACT PIN HAD SEPARATED FROM THE LANDING GEAR LEG. PORTIONS OF THE GEAR LEG RETRACT PIN BOSS AREA HAD SEPARATED AND WERE FOUND WEDGED ALONG SIDE THE GEAR ASSEMBLY. SUBSEQUENT METALLURGICAL INVESTIGATION REVEALED THE PIN BOSS AREA HAD METAL FRACTURE FEATURES CONSISTENT WITH OVERLOAD, ONE OF WHICH WAS CONSISTENT WITH A PREEXISTING FRACTURE AREA. THE PIN BOSS AREA HAD PREVIOUSLY BEEN OVER-BORED AND CHROME PLATED PRIOR TO A RETURN TO SERVICE. THE AIRPLANE MANUFACTURER STATED THE PIN BOSS BORE SHOULD NOT BE CHROME PLATED.
Probable cause
AN IMPROPER REPAIR OF THE RETRACT PIN BOSS AREA BY THE OVERHAUL FACILITY.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI93IA035
- Event ID
- 20001211X16010
- Case number
- CHI93IA035
- 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: e4df17f8af2d3b15dcd2b7f48accd247185b4df1105c2591707179cc2583db54; retrieved 2026-09-18T18:43:03.340Z.