# NTSB Accident SEA02LA121
> **Grumman-Schweizer G-164B** · 2002-07-04 · Shelley, ID, USA · MINR
## Event
- **NTSB number:** SEA02LA121
- **Event ID:** 20020715X01126
- **Type:** Accident
- **Date:** 2002-07-04
- **Location:** Shelley, ID, USA
- **Coordinates:** 43.45, -112.166664
## Injuries
- **Highest injury:** MINR
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 1
- **Uninjured:** 0
- **Total aboard:** 1
## Aircraft
- **Make:** Grumman-Schweizer
- **Model:** G-164B
- **Registration:** N297AL
- **FAR Part:** 137
- **Engines:** 1
- **Damage:** DEST
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

A loss of engine power due to the manufacturer's improperly machined threads, which prevented the cylinder base/head halves from being properly assembled, leading to fatigue propagation and the ultimate separation of the cylinder.  A contributing factor was the rough terrain.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=SEA02LA121) · AI Analytics · CC0 1.0*