# NTSB Accident FTW89LA031
> **MBB BO-105** · 1988-12-05 · SOUTH MARSH 113 · MINR
## Event
- **NTSB number:** FTW89LA031
- **Event ID:** 20001213X27426
- **Type:** Accident
- **Date:** 1988-12-05
- **Location:** SOUTH MARSH 113
## Injuries
- **Highest injury:** MINR
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 1
- **Uninjured:** 3
- **Total aboard:** 4
## Aircraft
- **Make:** MBB
- **Model:** BO-105
- **Registration:** N2785B
- **FAR Part:** 135
- **Engines:** 2
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

FAILURE AND SEPARATION OF ONE OF THE TAIL ROTOR BLADES FOR UNDETERMINED REASONS. THR RESULTING IMBALANCE AND VIBRATION CAUSED THE SEPARATION OF THE 90 DEGREE GEARBOX AND A PORTION OF THE VERTICAL PYLON WHICH NECESSITATED THE EMERGENCY AUTOROTATION TO THE WATER.

---
*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=FTW89LA031) · AI Analytics · CC0 1.0*