The Learjet 35A departed Campo de Marte Airport on a positioning flight to Rio de Janeiro (SDU). The takeoff clearance from runway 30 was issued at 14:08, and the flightcrew was advised the wind was from 300 degrees at 2 knots. The airplane was observed to begin the takeoff on runway 30 from the threshold, and after rotation, the tower controller noted the airplane pitched up steeply, then rolled quickly to the right an estimated 90 degrees. The airplane began a right descending turn, then rolled left and continued descending. At 14:09, the tower controller advised the flightcrew that the turn should be to the left. The flightcrew did not respond nor did they declare an emergency. The airplane impacted in a residential area in a nearly vertical trajectory, and 3 homes (near on the Rua Bernardino de Sena, 104) were damaged. Weather reported at the airport at 16:00Z (14:00 local time) included a temperature of 22 deg C, dewpoint 18 deg C, 1012.9 hPa, 4500 m visibility in light rain and mist, broken clouds at 1,400 ft. and overcast at 10,000 ft. Contributing Factors 1 Human Factor 1.1 Medical Aspect A) Fatigue – undetermined The copilot had only slept for five hours the night before, but no other factors were found that could prove to have degraded his performance. 1.2 Psychological Aspect A) Disregard of standards and procedures – contributed The pilot did not accompany the copilot in the preparatory procedures of the aircraft, even though he was aware that the copilot was still under training; and the checklist was not read. Such facts allowed fuel balancing to be generated and unidentified. B) Division of tasks – contributed There was inadequate prioritization of tasks on the part of the crew, where knowledge and experience were not efficiently used in the preparation of the flight, creating a condition unfavorable to flight (fuel imbalance). C) Excess of confidence – contributed The high level of experience on the aircraft made the pilot (commander and instructor) disregard the need to read the checklist for the normal procedures. D) Organization of work – contributed The pilot was responsible for coordinating the flight, for coordinating ground activities and for training the co-pilot, assuming assignments that should have been shared by the company. E) Loss of situational awareness – contributed The pilot was focusing his attention on coordinating the flight with the pilot of the helicopter that was in Angra dos Reis, failing to realize the dangerous condition (aircraft in critical condition of fuel imbalance) during the phases of preparation of cabin and taxi. 1.3 Operational Aspect A) Application of the commands – contributed After the takeoff, the pilot who was working on the controls established a rather steep attitude (20 ø or more), preventing the speed reaching values above 137KIAS, in order to obtain a better control of the aircraft with smaller amplitudes of aileron, besides of bringing the aircraft into the stall condition. B) Coordination of cabin – contributed The pilot (commander and instructor) did not properly coordinate the execution of the tasks, allowing the co-pilot in training to perform non-standard procedures, such as carrying out preflight checks wiihout supervision. The commander performed tasks that were not commensurate with the operation phase (talking on the cell phone while the taxiing). These events gave rise to a hazardous condition (critical fuel imbalance during preflight preparation). C) Instruction – contributed Whether intentionally or not, the standby pump and the cross flow valve were switched on for approximately 3 minutes during cockpit preparation by the co-pilot who, despite being trained in the aircraft, was alone in the cockpit without proper supervision of the instructor. The instruction was being performed without reading the checklist, which eliminated the chances of the error being identified. Failure to carry out simulator instruction, as provided for in IAC 135-1002, has contributed to the lack of correction of the lack of reading of the checklist by the captain and co-pilot. D) Pilot trial – contributed The pilot inadequately judged that the co-pilot in training did not require instructor supervision during preflight. E) Little pilot experience – contributed Unlike the pilot, who had extensive experience in the Learjet 35A aircraft, the co-pilot still completed the initial training because he was in the process of adapting to the operating characteristics of this type of aircraft. The low experience of the co-pilot, coupled with the lack of simulator training, contributed to a degraded performance against the normal and emergency operations of the aircraft during the crash. 2 Material Factor A) Project – Undetermined. The Learjet 35A aircraft manuals do not present a fuel imbalance limit for takeoff, although wingtip tank features require special attention. However, it is not possible to ensure that the crew would check this parameter if it was defined in the manual. The characteristics of the fuel system control panel, which do not allow the pilot to know the exact quantity