United Feeder Services Flight 5112
British Aerospace ATP · Incident: fire while standing
From South Bend International Airport (SBN) to Chicago O'Hare International Airport (ORD)
Event
- NTSB case
- CHI94IA066
- 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
British Aerospace ATP
- Aircraft type
- British Aerospace ATP
- 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
- N857AW
- Operator
- United Feeder Services
- Onboard fatalities
- Unknown
- Route
- From South Bend International Airport (SBN)To Chicago O'Hare International Airport (ORD), Chicago, IL
- 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
- Standing
- 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
- Fire
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- None
Cause areas
- Auxiliary power unit › Failure, total
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
AN AUTO SHUTDOWN OF THE AUXILIARY POWER UNIT (APU) OCCURRED. THERE WERE NO INDICATIONS OF A PROBLEM WITH THE APU SO THE CAPTAIN ATTEMPTED A RESTART TO NO AVAIL. THE COCKPIT CREW WAS THEN INFORMED THAT THE APU WAS ON FIRE. THE CAPTAIN BLEW THE APU FIRE BOTTLE AND THE AIRPLANE WAS EVACUATED WITHOUT FURTHER INCIDENT. EXAMINATION OF THE APU REVEALED A HOLE THROUGH THE TURBINE NOZZLE VANE PLATFORM WHICH RESULTED IN THERMAL FAILURE OF THE TURBINE WHEEL BLADES.
Probable cause
an internal failure of the auxiliary power unit.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI94IA066
- Event ID
- 20001206X00603
- Case number
- CHI94IA066
- 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, damage. 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: a8dd96626ed54729f5d7ad389b52531757702aace2d221502904aec4d6429b56; retrieved 2026-09-18T18:23:40.533Z.