What happened
On January 11, 2003, a TL-2000 Sting micro light aeroplane, registration PH-3S5, crashed shortly after takeoff near Grubbenvorst, Netherlands. The aircraft, which was nearly new with only a few flight hours, was being operated for a training flight. On board were the owner, who was undergoing a check-out by an instructor, and the instructor. The pilot had significant prior experience as a fighter pilot in the Royal Netherlands Air Force, though he was not yet licensed for this specific aircraft type.
After performing several circuits at an airfield dedicated to ultralight aircraft, the aircraft attempted a takeoff climb. A witness observed the aircraft banking to the right, following a pattern common to the instructor's flying style. As the aircraft passed over a hangar at an altitude of approximately 25 to 30 meters, the engine was heard to falter. The aircraft then disappeared from view with an unusually high nose attitude of about 45 degrees, eventually crashing approximately 30 meters from the building.
The investigation
Because micro light aeroplanes are not certified under international airworthiness standards, the investigation was limited in scope. Technical examination of the wreckage revealed that the flaps were fully retracted, despite the flight manual recommending 15 degrees of flaps for takeoff. The propeller blades were found in a fine pitch setting, which is standard for takeoff, but the damage to the blades suggested the engine was likely stationary when the propeller struck the ground.
Investigators found no visible traces of fuel in the engine, though the presence of a slight fuel odor was noted, which could have been attributed to unusable fuel. An electronic flight data recorder (FlyDat) was recovered but was too damaged to retrieve data. Additionally, there were conflicting reports regarding fuel availability at the airfield; while some claimed fuel was available, others suggested the crew had transported their own fuel in jerrycans.
Findings
- The engine experienced a momentary loss of power, which may have been caused by fuel starvation.
- The aircraft was flying at a low altitude and low airspeed over buildings at the time of the engine failure.
- The use of fully retracted flaps instead of the recommended 15 degrees of flaps likely increased the stall speed and negatively impacted the aircraft's performance during the critical climb phase.
- The instructor's habit of banking right immediately after takeoff to avoid power lines placed the aircraft in a position of low altitude over structures during the engine malfunction.
- An onboard emergency parachute system was likely not deployed due to the insufficient time available following the engine failure.