CHI04LA145 · Betchan KR II
Betchan KR II · Accident: loss of engine power during initial climb
From Rapid City Regional Airport (RAP) to an unrecorded destination
Event
- NTSB case
- CHI04LA145
- 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
- Unknown
- 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
Betchan KR II
- Aircraft type
- Betchan KR
- 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
- N250KB
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Rapid City Regional Airport (RAP), Rapid City, SDTo 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
- Initial climb
- 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
- Stall
- 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, rocker arm/tappet › Separation
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The amateur-built airplane was destroyed by an in-flight collision with terrain during a forced landing following a loss of engine power. The pilot reported that the takeoff was routine through 300-400 feet above ground level (agl) when the engine lost and then regained power. He was attempting to return to the airport when the engine lost power again. He reportedly turned to the left in order to avoid some hills in front of the aircraft. He maneuvered the aircraft again to avoid power lines "only to stall-slide into the terrain." The aircraft impacted the side of a small hill less than one-quarter mile west of the airport. A post-accident examination revealed that the left valve cover and rocker arms had separated from the engine. The valve cover and three of the four rocker arms were present in the vicinity of the engine. The fourth rocker arm was not located. The left side valve push rods had also separated from the engine and were located in the debris. The valve cover was dented in a manner consistent with impacts to the internal side of the cover.
Probable cause
Failure of the engine rocker arm installation resulting in a loss of engine power. A contributing factor was the power lines.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI04LA145
- Event ID
- 20040609X00774
- Case number
- CHI04LA145
- 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, coordinates. 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: 5e151ffea09706226fe341d654b8a7fd11d6c92fb2bfd79b7c23028dd07a9bb2; retrieved 2026-09-21T19:13:30.258Z.