What happened
On August 4, 2012, an EMB-810D Embraer Neiva, registration PT-VQW, was preparing for departure from Aeródromo Aéreo Amazônia (SSXN) in Altamira, Brazil. Prior to takeoff, the pilot noted dew formation on the aircraft windshield. Although the pilot cleared the condensation using paper during the pre-flight inspection, the windshield fogged up again immediately after the aircraft aligned with runway 07/25.
During the takeoff roll, the condensation intensified, causing the pilot to lose visual contact with the runway. At a speed of approximately 45 knots and roughly 300 meters into the takeoff run, the pilot noticed an unusual noise and a leftward deviation of the aircraft. The pilot reacted by applying right rudder, reducing power, and cutting the engines. The aircraft came to a stop on the runway, but the maneuver resulted in damage to the propellers and the left main landing gear door. The pilot and one passenger were uninjured.
The investigation
CENIPA investigators examined the meteorological conditions and the runway infrastructure. Although the local airfield lacked a weather station, data from the nearby Alta Floresta (SBAT) station indicated a saturated atmosphere, with temperatures and dew points nearly identical (17°C/17°C), which highly favored condensation and fog formation.
Additionally, the investigation identified a longitudinal drainage ditch located on the left side of the runway within the prepared surface area. The investigation also confirmed that the pilot was properly licensed, the aircraft was airworthy, and all maintenance records were up to date.