ASN Wikibase Occurrence # 308095
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Saturday 30 July 2005 |
| Time: | |
| Type: |  Aerospatiale AS 350B2 Ecureuil |
| Owner/operator: | Aeronorte |
| Registration: | CS-HES |
| MSN: | 2224 |
| Year of manufacture: | 1989 |
| Fatalities: | Fatalities: 0 / Occupants: 1 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | Ervacoes -
 Portugal
|
| Phase: | Manoeuvring (airshow, firefighting, ag.ops.) |
| Nature: | Fire fighting |
| Departure airport: | |
| Investigating agency: | GPIAA |
| Confidence Rating: |  Accident investigation report completed and information captured |
The Eurocopter AS 350 B2 helicopter, registration CS-HES, suffered an accident while fighting a forest fire, in Padrela mountain, near Lamas, municipality of Valpaços.
The helicopter was owned by Heliportugal and operated by Aeronorte for the Serviço Nacional de Bombeiros e Protecção Civil (SNBPC).
While performing a water drop with the Isolair water bombardment system, the pilot lost directional control of the helicopter in flight, and the helicopter went into rotation at a low altitude.
The main rotor blades and horizontal stabilizer collided with some bushes, and immediately fell to the ground.
The aircraft suffered severe damage to the tail, main rotor, tail rotor, Main Drive Gearbox support and right hand skid.
The pilot, the only occupant, was unharmed.
Primary Cause
The primary cause of this accident was the loss of transmission to the helicopter's tail rotor, which made directional control impossible. This transmission loss was due to the detachment of the transmission shaft, caused by the deformation of the tail cone structure, after the crash of the pump and water refueling valve assembly, due to a sudden maneuver by the pilot, in order to recover from an uncommanded sinking of the aircraft.
Ancillary Causes
Contributory factors were
1º. The orographic effect on the wind circulation that caused the creation of descending currents, close to the slope, which contributed to the sinking of the aircraft;
2º. The planning of the approach maneuver to the water discharge, which did not consider the mountain effect on wind circulation, and exposed the aircraft to that same effect;
3º. The abrupt recovery maneuver, using emergency power, without considering the balancing reaction of the water refueling set.
Accident investigation:
 |
|
Sources:
GPIAA
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 08-Jun-2023 06:01 | HanayoPlus | Updated |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation