FTW85LA111 · Aerospatiale AS 355F-1
Aerospatiale AS 355F-1 · Accident: partial loss of engine power (non-mechanical) en route
Event
- NTSB case
- FTW85LA111
- 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
- Accident
- 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
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Instrument Meteorological Cond
Aerospatiale AS 355F-1
- Aircraft type
- Aerospatiale AS-355
- Category
- Helicopter
- 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
- N5796A
- Operator
- Unknown
- 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 91: General Aviation
- 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 · 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
- Partial 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
- Substantial
Cause areas
- Pilot in command › Planning/decision, improper
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
WHILE EN ROUTE AT AN ALT OF 500 TO 700 FT, THE #1 ENG SPOOLED DOWN. THE PLT SECURED THE #1 ENG & TURNED BACK TOWARD THE HELIPORT TO MAKE A SINGLE ENG LANDING. HOWEVER, HE COULD NOT MAINTAIN LEVEL FLT & THE ROTOR RPM BEGAN DROPPING. THE PLT NOTED THAT THE #2 ENG HAD HI TEMP (ABOVE 900 DEGS) & LOW TORQUE. SUBSEQUENTLY, HE INFLATED THE POPOUT FLOATS & MADE A PARTIAL POWER LANDING IN A MARSH. DUE TO LOW ROTOR RPM, THE HELICOPTER TOUCHED DOWN HARD & WAS DAMAGED. THE #1 ENG WAS REMOVED & CHECKED IN A TEST CELL & IT OPERATED NORMALLY. THE #2 ENG WAS DAMAGED; HOWEVER, IT'S FUEL MANAGEMENT SYS CHECKED NORMAL. THE ACFT WAS BEING FLOWN IN RAIN SHOWERS WITHOUT USING THE ENG ANTI-ICE. OPERATOR PERSONNEL SUSPECTED THAT INLET ICING CAUSED THE #1 ENG TO FLAME OUT & THE #2 ENG TO LOSE PARTIAL POWER. A WITNESS ESTIMATED THE SURFACE AIR TEMP WAS 33 DEGS.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record FTW85LA111
- Event ID
- 20001214X35696
- Case number
- FTW85LA111
- 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: 6f35731becfb54dd2524d7127211e2dd8d4c7979e1331496c5aa0f3040b7e5a4; retrieved 2026-09-23T18:37:11.457Z.