# NTSB Accident CHI99FA120
> **Extra Flugzeugbau 300S** · 1999-03-24 · DOW, IL, USA · NONE
## Event
- **NTSB number:** CHI99FA120
- **Event ID:** 20001205X00275
- **Type:** Accident
- **Date:** 1999-03-24
- **Location:** DOW, IL, USA
- **Coordinates:** 38.999217, -90.330337
## Injuries
- **Highest injury:** NONE
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 1
- **Total aboard:** 1
## Aircraft
- **Make:** Extra Flugzeugbau
- **Model:** 300S
- **Registration:** N9K
- **FAR Part:** 091
- **Engines:** 1
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

a fatigue failure of the upper left longeron and adjacent diagonal cross member near the horizontal stabilizer attach point.  A factor related to the accident was that the manufacturer informed the operator that they were already in compliance with the latest revision of a service bulletin because they had complied with a previous revision.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=CHI99FA120) · AI Analytics · CC0 1.0*