# NTSB Accident WPR21LA040
> **SCHLEICHER ASW20C** · 2020-11-07 · Clayton, CA, USA · SERS
## Event
- **NTSB number:** WPR21LA040
- **Event ID:** 20201109102252
- **Type:** Accident
- **Date:** 2020-11-07
- **Location:** Clayton, CA, USA
- **Coordinates:** 37.839997, -121.87482
## Injuries
- **Highest injury:** SERS
- **Fatal:** 0
- **Serious:** 2
- **Minor:** 0
- **Uninjured:** 0
- **Total aboard:** 2
## Aircraft
- **Make:** SCHLEICHER
- **Model:** ASW20C
- **Registration:** N18MA
- **FAR Part:** 091
- **Engines:** 0
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

The failure of both pilots of each glider to see an avoid one another while maneuvering, which resulted in a mid-air collision.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=WPR21LA040) · AI Analytics · CC0 1.0*