# NTSB Accident LAX91LA375
> **BEIERLE THUNDER GULL J** · 1991-08-24 · SANTA MARGARITA, CA, USA · SERS
## Event
- **NTSB number:** LAX91LA375
- **Event ID:** 20001212X17916
- **Type:** Accident
- **Date:** 1991-08-24
- **Location:** SANTA MARGARITA, CA, USA
- **Coordinates:** 35.309906, -120.270149
## Injuries
- **Highest injury:** SERS
- **Fatal:** 0
- **Serious:** 1
- **Minor:** 1
- **Uninjured:** 0
- **Total aboard:** 2
## Aircraft
- **Make:** BEIERLE
- **Model:** THUNDER GULL J
- **Registration:** UNREG
- **FAR Part:** 091
- **Engines:** 1
- **Damage:** DEST
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

THE FAILURE OF THE WING SPAR WHEN THE DESIGN LIMITS OF THE AIRPLANE WAS EXCEEDED BY THE PILOT. CONTRIBUTING TO THE ACCIDENT WAS AN INADEQUATE AIRFRAME DESIGN AND AN ABRUPT MOVEMENT OF THE FLIGHT CONTROLS BY THE PILOT.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=LAX91LA375) · AI Analytics · CC0 1.0*