The aircraft took off from SBSP bound for Curitiba, with scheduled stopovers in Ponta Grossa and Cascavel. Due to the weather conditions in Ponta Grossa, a go-around was performed to circle and attempt landing on the opposite runway. During the approach the aircraft proceeded to the landing with the landing gear retracted. The aircraft touched down on the runway with the landing gear retracted. The passengers and crew exited the aircraft after it had stopped, via the emergency exit, with no personal injuries sustained. Contributing Factors a. Human Factor (1) Psychological Aspect: The presence of this factor contributed to variables at the individual level, with no involvement of those that could be present at the psychosocial and organizational levels. Regarding the individual-level variables, they encompassed aspects of affectivity (anxiety), activity (disregard for established procedures), motivation (compulsion to land), attention (interruption of work sequence and fixation of attention), memory (forgetfulness), management (poor cockpit coordination), cognition (making the wrong decision), and finally, stress (excessive stimuli). b. Material Factor Did not contribute. c. Operational Factor (1) Deficient Maintenance and Supervision: The repair service in the flap area was inadequate, indicating a failure in the quality of the inspection department. The installation of an “L/G Rezay Box” with an incompatible part number compared to the one previously installed on the aircraft demonstrates a deficiency in control. (2) Poor Cockpit Coordination: The crew did not follow standardized and pre-established procedures, turning their actions into individual and uncoordinated acts. (3) Adverse Weather Conditions: Although the weather was within IFR (Instrument Flight Rules) minimums, it quickly became an adverse factor following the go-around, potentially leading to a hasty decision-making process by the pilot. (4) Forgetfulness: It was the final link in the chain of events. It was primarily triggered by high levels of anxiety, increased workload, and cabin discoordination. (5) Poor Planning: The crew did not plan for the execution of a nighttime visual approach and was therefore unprepared to carry it out. (6) Poor Judgment: There was a failure in the pilot’s judgment during the operation. Initially, there were conditions that did not allow for the continuation of the landing, yet it was proceeded with. Finally, the nighttime visual approach was entirely unfavorable, and nonetheless, it was attempted.