# NTSB Accident NYC91FA067
> **MBB BK 117 B-1** · 1991-01-27 · SONESTOWN, PA, USA · FATL
## Event
- **NTSB number:** NYC91FA067
- **Event ID:** 20001212X16367
- **Type:** Accident
- **Date:** 1991-01-27
- **Location:** SONESTOWN, PA, USA
## Injuries
- **Highest injury:** FATL
- **Fatal:** 4
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 0
- **Total aboard:** 4
## Aircraft
- **Make:** MBB
- **Model:** BK 117 B-1
- **Registration:** N891GM
- **FAR Part:** 091
- **Engines:** 2
- **Damage:** DEST
## Conditions
- **Light:** NDRK
- **Weather:** IMC
## Probable cause

THE PILOT'S INADEQUATE PREFLIGHT PLANNING TO ASSURE THAT THE INTENDED COURSE AND ALTITUDE PROVIDED ADEQUATE TERRAIN CLEARANCE. CONTRIBUTING FACTOR(S) WAS: THE DARK NIGHT, SNOW AND MOUNTAINOUS TERRAIN.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=NYC91FA067) · AI Analytics · CC0 1.0*