Loss of control Accident de Havilland Canada DHC-6 Twin Otter 300 F-OGES,

ASN Wikibase Occurrence # 323319

Date:	Saturday 24 March 2001
Time:	16:28
Type:	de Havilland Canada DHC-6 Twin Otter 300
Owner/operator:	Air Caraïbes
Registration:	F-OGES
MSN:	254
Year of manufacture:	1969
Total airframe hrs:	35680 hours
Cycles:	89331 flights
Engine model:	Pratt & Whitney Canada PT6A-27
Fatalities:	Fatalities: 19 / Occupants: 19
Other fatalities:	1
Aircraft damage:	Destroyed, written off
Category:	Accident
Location:	Saint-Barthélémy - Saint Barth�lemy
Phase:	Approach
Nature:	Passenger - Scheduled
Departure airport:	Sint Maarten-Juliana Airport (SXM/TNCM)
Destination airport:	Saint-Barthélémy Airport (SBH/TFFJ)
Investigating agency:	BEA
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
The Twin Otter plane was on a 10-minute inter island flight between St. Maarten and Saint-Barthélémy and approached Saint-Barthélémy from the West for a visual approach and landing on runway 10. While on finals over the 'Col de la Tourmente', the aircraft was seen making a sharp turn to the left. The Twin Otter struck a house on the 'Col de la Tourmente' and caught fire. A man on the ground was also killed and his wife was injured. While on finals the captain probably
selected "beta reverse range" on the propellers in order to slow down. Upon vigorously pushing back the power levers to their normal position, an asymmetric power condition developed. The Twin Otter rolled to the left and crashed.
Saint-Barthélémy is known for the difficult approach to the airport and pilots flying into Saint-Barthélémy need to have a special certification. After overflying 'Col de la Tourmente' a quick steep descent has to be made to land at runway 10, a 2100 feet runway which ends up in sea. The aircraft overfly the 'Col de la Tourmente' at a height of 10 m or less.

PROBABLE CAUSES: "The accident appears to result from the Captain's use of the propellers in the reverse beta range, to improve control of his track on short final. A strong thrust asymmetry at the moment when coming out of the reverse beta range would have caused the loss of yaw control, then roll control of the aircraft.
The investigation could not exclude three other hypotheses which can nevertheless be classified as quite unlikely:
- A loss of control during a go-around.
- A loss of control due to a stall.
- A loss of control due to sudden incapacitation of one of the pilots.
The Captain's lack of recent experience on this airplane type, the undeniable difficulty of conducting an approach to runway 10 at Saint-Barthélemy and the pressure of time during this flight were contributory factors. The low height at which the loss of control occurred was an aggravating factor."

Accident investigation: