Aerodynamic stall during takeoff involving overweight aircraft

No fatalities • Unalaska-Tom Madsen (Dutch Harbor), United States of America • Takeoff (climb)

An aircraft experienced an aerodynamic stall and subsequent ocean impact during a downwind takeoff due to excessive weight and an aft center of gravity.

What happened

During the takeoff roll, the pilot of the aircraft applied back pressure once the airspeed reached approximately 90 knots. Although a brief positive rate of climb was initially noted, the aircraft began to sink as airspeed rapidly decreased. This was followed by the activation of the stall warning horn. In an attempt to recover the decaying airspeed, the pilot lowered the nose and leveled the wings, but the aircraft ultimately impacted the ocean.

At the time of the accident, wind conditions were recorded at 15 knots, with gusts reaching 28 knots, blowing from a direction 110 degrees downwind of the aircraft's path. While the pilot had briefed passengers regarding the downwind takeoff, there was no discussion regarding how these wind conditions might impact the takeoff performance. The pilot reported no mechanical malfunctions or anomalies prior to the event.

Findings

Investigation into the aircraft's configuration revealed that the estimated gross weight was approximately 769.6 pounds above the approved maximum limit. Additionally, the estimated center of gravity was approximately 8.24 inches beyond the approved aft limit for the maximum gross weight. These factors, combined with the decision to perform a downwind takeoff, likely caused the aerodynamic stall and subsequent loss of control.

Further examination of the operator revealed several instances of noncompliance with operational procedures. These included operating overweight flights, maintaining inaccurate or incomplete flight logs, and the pilot's failure to perform a required flight risk assessment. While the operator maintained a safety management system, the investigation concluded that the program was insufficient to effectively monitor and mitigate such operational hazards.

Probable cause

The aircraft entered an aerodynamic stall during takeoff due to the combination of operating significantly over the maximum gross weight, an aft center of gravity, and performing a downwind takeoff.

Frequently asked questions

What happened in the 2020-01-16 Beechcraft 200 Super King Air accident near Unalaska-Tom Madsen (Dutch Harbor), United States of America?

An aircraft experienced an aerodynamic stall and subsequent ocean impact during a downwind takeoff due to excessive weight and an aft center of gravity.

Were there any fatalities in the 2020-01-16 Beechcraft 200 Super King Air accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 2020-01-16 involved a Beechcraft 200 Super King Air, registration N547LM, operated by LifeMed Alaska, at Unalaska-Tom Madsen (Dutch Harbor), United States of America.

What was the probable cause of the accident?

The aircraft entered an aerodynamic stall during takeoff due to the combination of operating significantly over the maximum gross weight, an aft center of gravity, and performing a downwind takeoff.

Loading the flight search…