CHI98LA002 · Mikowski CHALLENGER II S CHALLENGER
Mikowski CHALLENGER II S CHALLENGER · Accident: loss of control in flight while maneuvering
From Home Acres Sky Ranch Airport (Y91) to an unrecorded destination
Event
- NTSB case
- CHI98LA002
- 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
Mikowski CHALLENGER II S CHALLENGER
- Aircraft type
- Mikowski CHALLENGER
- Category
- Ultralight
- 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
- N19006
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Home Acres Sky Ranch Airport (Y91)To 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
- Loss of control in flight
- 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
- Tree(s)
- 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
- Fluid, fuel › Improper
- Pilot in command › Instructions, written/verbal, not followed
- Pilot in command › Refueling, improper
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot departed the airport for a short local flight. The pilot stated he throttled back and could no longer maintain control of the aircraft. He said he tried to increase the power, but the engine quit. He descended in a left bank into trees. The previous day the pilot added a door kit to the aircraft. The manufacturer of the kit recommends adding a rudder trim tab to the aircraft. No trim tab was found. Examination revealed that the fuel in the tank had 'excessive oil to fuel ratio.' The engine run unsuccessful until the spark plugs were changed.
Probable cause
the improper oil to gas mixture in the fuel during refueling and the pilot did not follow the written instructions from the kit manufacturer. Factors contributing to the accident were the pilot could not maintain directional control and the low altitude.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI98LA002
- Event ID
- 20001208X08963
- Case number
- CHI98LA002
- 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: 7bd1d7ba93db6e601fddc7087012a7a999a493c8937bdf3cb839163a658aa411; retrieved 2026-09-21T11:47:33.907Z.