The air traffic environment is a complex system that involves several players. Between the air navigation service provider (ANPS) and the final client, many different organizations act with different purposes but are strongly interfaced. Changes and modifications in terms of technology, predefined process, or personnel are constantly needed, requiring coordination among the stakeholders. However, due to the high level of interaction between the players, any change in a complex system like the air traffic environment requires risk management. This paper demonstrates the suitability and advantages of the System-Theoretic Accident Model and Processes/Systems-Theoretic Process Analysis (STAMP/STPA) method to be applied to the risk assessment of an operational air traffic modification. The method, which had never been used on an air traffic problem in Brazil before, was applied considering the implementation of segregated simultaneous operation at the Guarulhos International Airport. The results were proven to be effective in terms of deriving useful safety requirements. From such demonstration, STAMP/STPA can be considered as a feasible alternative to the brainstorming method currently applied for risk assessment and generation of safety requirements regarding modifications in the structure of the air traffic services (ATS) in Brazil.
The use of the required navigation performance (RNP) procedure has been increasing for aircraft navigation, since it allows for better optimisation of the airspace, which is increasingly congested. The present work aims to investigate the application of the functional resonance analysis method (FRAM), combined with the quantitative analysis provided by the Bayesian belief network (BBN), to demonstrate the existing variability in functions that are part of the complex navigation system based on the RNP procedure, specifically when the aircraft approaches the airport (approach phase). As a result, it is possible to analyse the variability that occurs in the studied system and the BBN complemented the study by allowing a quantitative interpretation of the functions considered most important for the execution of an RNP approach procedure.
This paper presents an evaluation of the influence of aircraft configuration on the boarding and deboarding times using a simplified model and computer simulation. Boarding and deboarding times are important to airlines since both procedures are part of the critical path of the turnaround time (TAT) of aircraft in airports. During the TAT, a series of activities are performed in the aircraft in order to prepare it for the next flight. A reduction in boarding and deboarding times may represent a reduction in TAT for airlines. For the comparisons, three aircraft configurations are used: single aisle
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(“six abreast”), single aisle
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(“five abreast”), and single aisle
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(“four abreast”), all with the same number of passengers. For the boarding analyses, two boarding procedures are used: random and random outside-in. The
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aircraft interior configuration holds the shortest boarding times; deboarding times are similar for the three configurations. Also, a sensitivity analysis is carried out, and the results show that the higher the aircraft occupancy and the number of passengers with carry-on baggage, the higher are boarding and deboarding times, with the
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having the lowest times in comparison with the other two configurations.
Purpose. This study aimed to analyse the correlations between individual technical determinants and the overall team performance in rink hockey sport. Methods. Retrospective observational data were collected from 182 matches played by 14 teams competing at the first division of the Portuguese national senior rink hockey championship (full season, 2018/19). Goals scored, goals conceded, direct free-hits, penalties, and final classifications were collected by team, on the basis of the official scoresheets of the games, validated by the official referees.Results. The results revealed that direct free-hits were more prevalent, although teams were more effective on penalties (40.4%) than direct free-hits (27.1%). Strong inverse relationships between direct free-hits effectiveness and final classification in the league (r = -0.71, p = 0.004) as well as penalties (r = -0.58, p = 0.029) were found. The effectiveness of the technical determinants, penalties, and direct free-hits increased with the proficiency of the teams in the classification. However, the bottom teams experienced significantly higher weights of these technical determinants on the team's total goals scored (1 st -4 th : 15.3%, 5 th -9 th : 25.6%, 10 th -14 th : 23.9%; p < 0.05). Conclusions. In conclusion, individual technical determinants' effectiveness was a strong predictor of team performance, accounting for at least 22.1% of the total goals scored in the full season, highlighting athletes' specialization in the training process.
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