Simmons Airlines Flight 3570
Saab-Scania AB (Saab) 340B · Incident: total loss of engine power (non-mechanical) en route
From Corpus Christi International Airport (CRP) to C David Campbell Field Corsicana Municipal Airport (CRS)
Narrative check · The NTSB narrative appears to contradict this record's departure or destination. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- FTW96IA045
- 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
Saab-Scania AB (Saab) 340B
- Aircraft type
- Saab Scania Ab (saab) 340
- 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
- N344SB
- Operator
- Simmons Airlines
- Onboard fatalities
- Unknown
- Route Possible conflict
- From Corpus Christi International Airport (CRP), Corpus Christi, TXTo C David Campbell Field Corsicana Municipal Airport (CRS), DALLAS/FT WORTH, TX
- 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 · descent
- 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
- Total loss of engine power (non-mechanical)
- 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
- Electrical system, fuse › Open
- Engine assembly › Ice ingestion
- Ignition system, auto re-light system › Inoperative
Approximate · Estimated position: the centre of Corsicana, TX, the place the record names. Not the accident site.
NTSB narrative
During descent, after exiting light icing conditions, the left engine lost power, & power fluctuations of the right engine were noted. The flightcrew declared an emergency, diverted to the nearest airport, & made an uneventful landing. There were indications of engine ice ingestion, but no engine damage. During ground runups, the right engine performed normally. The left engine ran normally, except its auto-ignition & overspeed protection were inoperative due to an open fuse in the Digital Electronic Control Unit (DECU). The open fuse would have prevented an automatic relight after a flameout. The Saab 340 fleet has a history of power losses associated with in-flight icing, dating back to 1985. The manufacturer (Saab) had determined that ice/slush could accumulate on the rear wall of the inlet protective device (bird catcher) & shed from the 'splitter lip' into the engine airflow path. As a preventive measure, Saab had developed an auto-ignition system to provide automatic relighting of the engine. Also, Saab was testing an improved heating system to prevent ice/slush from accumulating on the splitter lip. Title 14 CFR Part 25 requires that airplanes be designed so that engine inlet ice that would adversely affect engine operation cannot accumulate. During flight tests with the left engine inoperative & the propeller synchrophaser engaged, multiple power fluctuations of the right engine occurred. Instructions to turn the synchrophaser 'off' were not included in the engine failure checklist.
Probable cause
Total loss of power in the left engine from ice ingestion; and failure of the left-engine auto-relight system caused by an open fuse in the Digital Electronic Control Unit (DECU), which prevented an automatic relight of the left engine. Factors relating to the incident were: inadequate design of the engine air inlet anti-ice system, which allowed ice/slush accumulation; inadequate action by the FAA to ensure compliance with certification requirements regarding inlet ice accumulation; and an inadequate procedure in the flight manual concerning use of the engine synchrophaser during single-engine operation.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW96IA045
- Event ID
- 20001207X04842
- Case number
- FTW96IA045
- 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: 770db7cd1445c2998e253bdf646dc6ca1b59ccf8306a2d162cbb0e11d03c8ffc; retrieved 2026-09-18T17:56:12.204Z.