What happened
On October 18, 2014, at approximately 17:20 local time, a Cessna 150 G, registration CX-BGY, was performing a training flight at the Aero Club Tacuarembó in Uruguay. The flight involved a student pilot and an instructor. Following two successful touch-and-go landings, the crew attempted a short-field takeoff maneuver.
During the maneuver, the aircraft landed near the runway threshold. The crew retracted the flaps from 40° to 10° and applied maximum power. However, the aircraft failed to accelerate sufficiently to complete the takeoff. The instructor took control of the aircraft and applied maximum braking, but the plane could not be stopped within the paved or regularized area of the runway. The aircraft veered left, crossed a small ditch, and struck a perimeter fence, resulting in a rollover. Both the student pilot and the instructor evacuated the aircraft uninjured, though the aircraft sustained significant damage.
The investigation
The CIAIA investigation examined the environmental conditions, aircraft performance, and operational decisions. The investigation noted that the aircraft had not flown for 21 days due to adverse weather, and the runway surface was wet and partially waterlogged following recent heavy rains.
Investigators analyzed the aircraft's performance capabilities, noting that high temperatures (approximately 28°C) and high humidity significantly impacted takeoff distance. The investigation also identified secondary distractions within the cockpit, including an erroneous tachometer reading and an inoperative stall warning system. Furthermore, the investigation found that the aircraft was being operated at an excessive pitch attitude, evidenced by marks on the rudder and the tail dragging on the soft ground.
Findings
- The runway was a grass surface in a wet and degraded state, which increased takeoff distance requirements.
- A sudden change in wind direction occurred during the maneuver, negatively affecting the aircraft's performance.
- The crew's decision to perform a short-field takeoff did not sufficiently account for the cumulative penalties imposed by the wet grass, high temperature, and low pressure.
- The aircraft was unable to complete the takeoff within the remaining runway distance due to the extended ground time required for the short-field maneuver under adverse conditions.
- The aircraft was operating with a pitch attitude that caused the tail to scrape the ground, further increasing drag.