What happened
On 11 September 2011, a Piper PA-44-180 was conducting local training maneuvers at Brustem Airfield (EBST). The flight, operated by Ben-Air Flight Academy, included an instructor and two student pilots. The session was designed to practice single-engine procedures and minimum control airspeed (VMCA) demonstrations.
During a second touch-and-go maneuver, the crew initiated a simulated engine failure. While the student pilot initially managed the aircraft, the instructor took control during the landing phase when the student struggled to maintain the runway centerline. As the aircraft rolled along the runway, the instructor retracted the flaps in preparation for the next takeoff. At this moment, the aircraft veered sharply to the left toward a nearby embankment.
In an attempt to avoid the embankment, the instructor applied full power and rotated the aircraft. However, the plane could not gain sufficient speed or heading correction. The left wing subsequently stalled, striking the ground and causing the aircraft to cartwheel violently. The impact resulted in the total destruction of the aircraft, though all 3 persons on board escaped without injury.
The investigation
AAIU(Be) investigators examined the aircraft's mechanical state, the meteorological conditions, and the flight crew's actions. The investigation focused on why the aircraft experienced a sudden loss of directional control during the landing roll and why the engine's performance was compromised.
Technical analysis of the engines revealed that the left engine had actually become inoperative, contrary to the crew's belief that the failure was merely a simulation. The investigators also reviewed the flight school's training handbooks regarding the distinction between real and simulated engine failures, as well as the procedures for managing carburetor icing.
Findings
- The primary cause of the accident was a loss of control during a touch-and-go maneuver caused by an undetected inoperative engine.
- The left engine had failed due to carburetor icing, a condition facilitated by the ambient temperature and humidity.
- The sudden retraction of the flaps during the landing roll exacerbated the existing directional instability caused by the asymmetric thrust.
- The crew was operating under the false assumption that the engine failure was a planned simulation, meaning the actual loss of power was not recognized as a real emergency until the aircraft began to veer off the runway.