Purpose

The current air traffic management (ATM) operational approach is changing; “time” is now integrated as an additional fourth dimension on trajectories. This notion will impose on aircraft the compliance of accurate arrival times over designated checkpoints (CPs), called time windows (TWs). This paper aims to clarify the basic requirements and foundations for the practical implementation of this functional framework.

Design/methodology/approach

This paper reviews the operational deployment of 4D trajectories, by defining its relationship with other concepts and systems of the future ATM and communications, navigation and surveillance (CNS) context. This allows to establish the main tools that should be considered to ease the application of the 4D-trajectories approach. This paper appraises how 4D trajectories must be managed and planned (negotiation, synchronization, modification and verification processes). Then, based on the evolution of a simulated 4D trajectory, the necessary corrective measures by evaluating the degradation tolerances and conditions are described and introduced.

Findings

The proposed TWs model can control the time tolerance within less than 100 s along the passing CPs of a generic trajectory, which is in line with the expected future ATM time-performance requirements.

Originality/value

The main contribution of this work is the provision of a holistic vision of the systems and concepts that will be necessary to implement the new 4D-trajectory concept efficiently, thus enhancing performance. It also proposes tolerance windows for trajectory degradation, to understand both when an update is necessary and what are the conditions required for pilots and air traffic controllers to provide this update.

中文翻译：

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空中交通管理中4D轨迹的实际实现：系统要求和时间窗口监控

目的

当前的空中交通管理（ATM）运营方式正在发生变化；现在，“时间”已集成为轨迹的第四维度。该概念将使飞机符合在指定检查点（CP）上准确到达时间的要求，称为时间窗口（TWs）。本文旨在阐明此功能框架的实际实施的基本要求和基础。

设计/方法/方法

本文通过定义4D轨迹与未来ATM的其他概念和系统以及通信，导航和监视（CNS）上下文的关系来回顾其4D轨迹的操作部署。这样可以建立应考虑的主要工具，以简化4D轨迹方法的应用。本文评估了如何管理和计划4D轨迹（协商，同步，修改和验证过程）。然后，基于模拟的4D轨迹的演变，描述并介绍了通过评估退化容差和条件而采取的必要纠正措施。

发现

所提出的TWs模型可以沿着通用轨迹的通过CP将时间容限控制在不到100 s内，这符合预期的未来ATM时间性能要求。

创意/价值

这项工作的主要贡献是提供了系统和概念的整体视野，这对于有效地实现新的4D轨迹概念必不可少，从而提高了性能。它还提出了用于轨迹退化的公差窗口，以了解何时需要进行更新以及飞行员和空中交通管制员提供此更新所需的条件是什么。