CHI84LA279 · Bell 47G2
Bell 47G2 · Accident: partial loss of engine power (non-mechanical) while maneuvering
Event
- NTSB case
- CHI84LA279
- 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
- Visual Meteorological Cond
Bell 47G2
- Aircraft type
- Bell 47
- 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
- CFISH
- 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
- Maneuvering
- 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
- Destroyed
Cause areas
- Ignition system, spark plug › Corroded
- Ignition system, spark plug › Worn
- Pilot in command › Adequate rotor RPM, not maintained
- Pilot in command › Throttle/power control, improper use of
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE ACFT LANDED IN THE DETROIT RIVER AFTER THE ENGINE SPUTTERED AND THE ACFT VIBRATED. THE PLT REDUCED PWR & COLLECTIVE AND PUSHED THE CYCLIC FORWARD. THE RPM REDUCED FROM 3000 TO 2500 BUT THE ROTOR AND ENGINE RPM REMAINED MARRIED. THE PLT ADJUSTED DESCENT WITH COLLECTIVE, FORWARD SPEED WITH CYCLIC AND PULLED ALL COLLECTIVE JUST PRIOR TO IMPACT. THE ACFT WAS AT ABOUT 150 FT AGL WHEN THE ENGINE SPUTTERED. ONE PASSENGER DESCRIBED A SPUTTERING NOISE BUT SAID THE ENGINE WAS RUNNING UNTIL IMPACT. ANOTHER PASSENGER DESCRIBED THE ENGINE NOISE AS A MUFFLED MISFIRING SOUND. THE PASSENGERS ALSOSAID THE PLT DID NOT MENTION THE PROBLEM TO THEM AND THE HELICOPTER SEEMED UNDER CONTROL UNTIL IMPACT. POST ACCIDENT EXAMINATION OF THE ENGINE AFTER RECOVERY FROM THE WATER SHOWED THAT THE SPARK PLUGS WERE WORN AND CONTAINED A HEAVY BUILD-UP OF CARBON AND LEAD. NEAR THE OPERATORS HANGER WERE 5 SEALED AND 1 UNSEALED FUEL DRUMS WITH STANDING WATER ON THE TOPS. NO OTHER EVIDENCE WAS FOUND TO INDICATE ANY MALFUNCTION OF THE ACFT.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record CHI84LA279
- Event ID
- 20001214X40233
- Case number
- CHI84LA279
- 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: f4cb2e172ae8e567fd5c98f56a406ecc609e31f80942ada0b8a27128ebf24419; retrieved 2026-09-21T17:33:11.873Z.