CHI98FA353 · Barklage REVOLUTION MINI 500 REVOLUTION
Barklage REVOLUTION MINI 500 REVOLUTION · Accident: loss of engine power en route
From St Louis Downtown Airport (CPS) to 3SQ · ST. CHARLES, MO
Event
- NTSB case
- CHI98FA353
- 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
- 1 · 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
Barklage REVOLUTION MINI 500 REVOLUTION
- Aircraft type
- Barklage REVOLUTION MINI 500
- 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
- N611AB
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From St Louis Downtown Airport (CPS)To 3SQ · ST. CHARLES, MO
- 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 · climb to 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
- Loss of engine power
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Wire, transmission
- 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
- Engine assembly, piston › Seized
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
A witness watched the helicopter as it climbed out after takeoff. The witness said that the helicopter was higher than the telephone lines which ran northeast of the airport. 'He was level and climbing, going away from me when all of a sudden, the sound (engine sound) went quiet, followed by a pop. It was not a loud pop.' The helicopter began a shallow descent. At about 30 to 40 feet above the field, the helicopter 'leveled out,' but 'kept coming down.' The witness said he saw the helicopter 'hit' and then 'cartwheel.' Examination of the helicopter's engine revealed scoring marks on the power-takeoff cylinder (front cylinder) piston, and impact marks in the head. Small metallic particles were embedded in the piston head. The power-takeoff cylinder wall showed scuff marks, and the cylinder head showed impact marks. The two power-takeoff spark plugs' showed no gap at the electrodes, and impact marks. No other anomalies were revealed.
Probable cause
A loss of engine power due to cold seizure of the power-takeoff cylinder. A factor contributing to the accident was the power lines.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI98FA353
- Event ID
- 20001211X11011
- Case number
- CHI98FA353
- 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: 6f57109e45d4d306ebd71659901974d0057702858d937085200de046db76df11; retrieved 2026-09-20T22:25:00.677Z.