# NTSB Accident LAX91LA302
> **AIR TRACTOR AT-401** · 1991-07-10 · CALEXICO, CA, USA · MINR
## Event
- **NTSB number:** LAX91LA302
- **Event ID:** 20001212X17593
- **Type:** Accident
- **Date:** 1991-07-10
- **Location:** CALEXICO, CA, USA
- **Coordinates:** 32.690521, -115.51062
## Injuries
- **Highest injury:** MINR
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 1
- **Uninjured:** 0
- **Total aboard:** 1
## Aircraft
- **Make:** AIR TRACTOR
- **Model:** AT-401
- **Registration:** N4538K
- **FAR Part:** 137
- **Engines:** 1
- **Damage:** DEST
## Conditions
- **Light:** NDRK
- **Weather:** VMC
## Probable cause

THE ERECTION OF A CONSTRUCTION SIGN ON AN ACTIVE RUNWAY BY COUNTY WORKERS WITHOUT NOTIFYING THE AIRPORT OPERATORS, AND, THE INABILITY OF THE PILOT TO DETECT THE PRESENCE OF THE SIGN DURING THE DARK NIGHT TAKEOFF.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=LAX91LA302) · AI Analytics · CC0 1.0*