# NTSB CHI94IA066: British Aerospace ATP, N857AW, South Bend, IN, January 19, 1994 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: January 19, 1994, 17:40 local (22:40 UTC) - Place: South Bend, IN - Coordinates: 41.719875, -86.329025 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.7199&lon=-86.3290&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 33 uninjured - Status: Completed, report February 14, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 9398 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI94IA066 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/9398/pdf - Page: https://openairdocs.org/ntsb/CHI94IA066 ## Probable cause an internal failure of the auxiliary power unit. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Fire, standing - auxiliary power unit - failure,total (cause) - emergency procedure - performed, pilot in command - evacuation - initiated, pilot in command ## Analysis 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. ## Factual narrative On January 19, 1994, at 1740 eastern standard time, a British Aerospace ATP, N857AW, operated as United Express Flight 5112, experienced an Auxiliary Power Unit (APU) fire while on the ramp at the Michiana Airport, South Bend, Indiana. The airplane was being operated as a scheduled passenger flight under 14 CFR Part 121. An emergency evacuation was initiated following notification of the fire. The airplane was not damaged. The flight crew of 2, cabin crew of 2, and 29 passengers were not injured. The intended destination of the flight was Chicago, Illinois. The captain reported that while boarding the passengers an auto shutdown of the APU was experienced. He reported that he checked the APU system and all indications were normal so he performed the restart procedures. He stated that "someone" behind him then yelled, "The APU is on fire" at which time he activated the APU fire bottle. He stated he then left the cockpit to investigate the situation and the airplane was evacuated. The 'A' flight attendant reported hearing a "large pop & hiss..." while in the cabin. The flight attendant reported going into the cockpit to find out what the problem was. According to the flight attendant, the Captain stated there was a problem with the APU and he was going to investigate. The flight attendant continued to report, "When I was by the door and I heard people shouting there's a fire, there's a fire. So I turned to the Captain and asked if I should evacuate, and he said 'Immediately' so I evacuated through the forward exit." The 'B' flight attendant in the rear of the airplane reported she heard the noise and looked out the right aft door which was already opened. She stated she saw smoke to the left and people to the right yelling that there was a fire and to get everyone off the airplane. She stated she also heard a P/A announcement from the front to perform an emergency evacuation. She stated she checked for fire and not seeing any, opened the door and engaged the slide. All passengers were evacuated through the right rear door slide and the two forward exits without injury. Post accident inspection of the APU by Garrett determined, "The malfunction appears to have occurred because of hot gas corrosion of the turbine nozzle. There was a hole through the nozzle vane platform which caused thermo distress of the turbine wheel blades." ## Aircraft - Registration: [N857AW](https://openairdocs.org/deregistered/N857AW-2000-05-31), registration cancelled 2000-05-31, S/N 2034 (OpenAirDocs) - Reported make and model: BRITISH AEROSPACE ATP - Registry model: [British Aerospace BAE ATP](https://openairdocs.org/model/british-aerospace-bae-atp) (registry code 1500300) (OpenAirDocs) - Category: Airplane - Serial number: 2034 - Airframe hours: 4687 - Engines: P&W PW126A 2600 horsepower turbo prop - Damage: No damage - Fire: On-Ground - Flight: Part 121 - Operator: United Feeder Services, doing business as United Express - Registered owner: Air Wisconsin - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, January 19, 1994 - Departed: SBN - Destination: ORD, CHICAGO, IL - Flight plan: IFR - Airport: SBN, Michiana Regional ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 5,000 total, 156 in this make and model ## Weather - Conditions: Visual (VMC), Dusk - Wind: 200° at 8 knots - Visibility: 4 statute miles - Temperature: -2 °F, dew point -0 °F - Altimeter: 30.00 inHg - Observed at: SBN ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 19940119004509I](https://openairdocs.org/incident/19940119004509I), Jan 19, 1994: Bag ATP, South Bend, IN. Narrative: on January 19, 1994, at 1740 eastern standard time, a british aerospace Atp, N857AW, operated as united express flight 5112, experienced an APU fire… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.