# NTSB Accident DEN90LA123
> **PIPER PA-18-150** · 1990-06-04 · DOUGLAS, WY, USA · NONE
## Event
- **NTSB number:** DEN90LA123
- **Event ID:** 20001212X23380
- **Type:** Accident
- **Date:** 1990-06-04
- **Location:** DOUGLAS, WY, USA
- **Coordinates:** 42.749637, -105.389801
## Injuries
- **Highest injury:** NONE
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 1
- **Total aboard:** 1
## Aircraft
- **Make:** PIPER
- **Model:** PA-18-150
- **Registration:** N4720A
- **FAR Part:** 091
- **Engines:** 1
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

THE ACCIDENT TO BE IMPROPER INSTALLATION OF AILERON CONTROL SYSTEM BY MAINTENANCE PERSONNEL, AND FAILURE TO PERFORM AN AIRCRAFT PREFLIGHT BY THE PILOT IN COMMAND.

---
*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=DEN90LA123) · AI Analytics · CC0 1.0*