# NTSB Accident CHI05CA032
> **Olson Sonex** · 2004-11-21 · Oconomowoc, WI, USA · SERS
## Event
- **NTSB number:** CHI05CA032
- **Event ID:** 20041217X02002
- **Type:** Accident
- **Date:** 2004-11-21
- **Location:** Oconomowoc, WI, USA
- **Coordinates:** 43.109443, -88.486114
## Injuries
- **Highest injury:** SERS
- **Fatal:** 0
- **Serious:** 1
- **Minor:** 0
- **Uninjured:** 0
- **Total aboard:** 1
## Aircraft
- **Make:** Olson
- **Model:** Sonex
- **Registration:** N478SX
- **FAR Part:** 091
- **Engines:** 1
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

The loss of engine power due to a fatigue fracture of the crankshaft.  An additional cause to the accident was the pilot/builder's failure to verify the dimensions of the shrink-fit crankshaft components prior reassembling the engine.  A factor to the accident was the ditch encountered during the forced landing.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=CHI05CA032) · AI Analytics · CC0 1.0*