What happened
On October 10, 2008, a Cessna 337A, registration PT-WIR, was performing a takeoff from the Flores Aerodrome (SWFN) in Amazonas, Brazil, bound for Coari. After rotation and reaching an altitude of approximately 100 feet, the pilot lost control of the aircraft. The aircraft entered a nose-down attitude and returned to the runway, causing the propeller blades of the front engine to strike the ground.
Following the impact, the aircraft climbed briefly before the pilot shut down the engines while still over the runway. The aircraft eventually struck the ground approximately 50 meters beyond the runway threshold. The aircraft sustained severe damage, though the pilot remained uninjured.
The investigation
CENIPA investigators examined the aircraft's performance parameters and the pilot's experience. Although the pilot initially claimed a propeller blade had detached in flight, physical evidence—including longitudinal fractures on the propeller hub and marks on the runway—confirmed that the propeller strike occurred only after the aircraft made contact with the ground.
The investigation also reviewed the takeoff configuration. The pilot utilized 24 inches of manifold pressure (2,600 RPM) and rotated at 75 MPH. However, the aircraft owner, who was observing the takeoff, noted that the pilot failed to apply full power (28 inches of manifold pressure/2,800 RPM) and rotated too early. Given the short length of the runway (799 meters), the investigation determined that the aircraft lacked sufficient lift for sustained flight.
Findings
- The pilot had only one hour of flight experience in this specific aircraft type and was performing his first solo takeoff.
- The pilot applied insufficient power for the runway conditions, failing to reach the required rotation speed of 85 MPH.
- Inadequate takeoff parameters led to a loss of airspeed and subsequent aerodynamic stall.
- The pilot's decision to pull back on the control column during the loss of lift exacerbated the stall.
- The pilot's instruction and training process were insufficient to ensure safe operation of this aircraft type.