# NTSB Accident CHI88FA091
> **BEECH B90** · 1988-04-05 · ST. PAUL, MN, USA · NONE
## Event
- **NTSB number:** CHI88FA091
- **Event ID:** 20001213X25425
- **Type:** Accident
- **Date:** 1988-04-05
- **Location:** ST. PAUL, MN, USA
- **Coordinates:** 44.929679, -93.080429
## Injuries
- **Highest injury:** NONE
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 5
- **Total aboard:** 5
## Aircraft
- **Make:** BEECH
- **Model:** B90
- **Registration:** N181LL
- **FAR Part:** 135
- **Engines:** 2
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** IMC
## Probable cause

MECHANICAL FAILURE AND STICKING OF THE PILOTS THUMB OPERATED TRIM SWITCH CAUSING NOSE DOWN PITCH COMMAND. THE FAILURE OF THE CABIN HEATER AND THE LOW CABIN TEMPERATURE ARE CONTRIBUTING FACTORS.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=CHI88FA091) · AI Analytics · CC0 1.0*