What happened
On August 16, 2005, West Caribbean Airways flight WCW 708, an MD-82 with registration HK-4374X, was operating an instrument flight from Tocumen International Airport in Panama City to Fort-de-France, Martinique. The flight was proceeding under instrument flight rules (IFR) through weather conditions characterized by stratocumulus clouds and heavy precipitation.
While cruising at flight level 330, the aircraft began a continuous degradation of airspeed. As the speed decreased toward the minimum lift threshold, the aircraft entered a stall. This led to a subsequent uncontrolled descent, and the aircraft impacted the ground in a flat area near Machiques, Zulia State, Venezuela, at an elevation of approximately 119 feet.
The investigation
The investigation examined the flight's progression through several phases, including the initial climb, the cruise at flight level 310, the transition to flight level 330, and the final loss of airspeed and control. Investigators analyzed the aircraft's performance capabilities, specifically looking at how different takeoff weights and anti-ice configurations affected the maximum achievable altitude.
Technical analysis included a review of the flight data recorder (FDR) and cockpit voice recorder (CVR). The investigation also involved flight simulations to model the aircraft's trajectory and evaluated the engine performance and thrust requirements at various Mach numbers. Additionally, the investigation reviewed the company's accident history and the meteorological conditions present at the time of the accident, including satellite imagery of convective tropical systems in the region.
Findings
- The aircraft experienced a continuous loss of airspeed while at cruise altitude.
- The aircraft entered a stall state following the loss of sufficient velocity to maintain lift.
- The flight was operating in an area with significant tropical convective activity and heavy precipitation.
- Performance studies indicated that the use of engine and wing anti-ice systems significantly impacts the maximum achievable altitude for various takeoff weights.