ABSTRACT

Objective: This study aims at investigating helicopter pilots’ strategies to achieve ship deck landing.

Background: Helicopter maritime operations are challenging, especially when it comes to landing on the moving decks of small ships, such as frigates, which can lead to dramatic accidents.

Method: Expert pilots were requested to fly the full ship landing maneuver from approach to touchdown in an immersive simulator. Two sea states (3 and 4 on the Douglas Sea scale) and their resulting deck movements were used. Changes in helicopter altitude were correlated with deck heave movements throughout the maneuvers in order to scrutinize the helicopter-deck coupling. The energy at impact was measured.

Results: The dynamics of helicopter-deck coupling evolved through two phases during the maneuver: Initially, no coupling then, coupling in phase between the helicopter vertical displacements and deck heave displacements. Moreover, the coupling reached higher values within the last 15 m to landing, corresponding to a hover phase and touchdown, and the correlation increased with sea level. This coupling might help in improving pilots’ safety since the greater the coupling at touchdown, the lesser the kinetic energy at impact.

Conclusion: Coupling the helicopter vertical displacements with ship heave movements seems to be an efficient strategy to minimize energy at impact. Questions arise on both the rationale and the perceptual invariant behind such behavior and indicate the necessity of further investigation.

摘要

目的：本研究旨在调查直升机飞行员实现舰艇甲板着陆的策略。

背景：直升机的海上作业具有挑战性，尤其是在诸如护卫舰等小型船舶的移动甲板上着陆时，这可能导致重大事故。

方法：要求专业飞行员在沉浸式模拟器中进行从进场到着陆的全船着陆操作。使用了两个海州（道格拉斯海标尺上的3和4）及其产生的甲板运动。直升机高度的变化与整个演习中的甲板升沉运动相关，以便检查直升机-甲板之间的连接。测量了冲击能量。

结果：在操纵过程中，直升机-甲板耦合的动力学过程经历了两个阶段：最初没有耦合，然后在直升机垂直位移和甲板升沉位移之间进行了相位耦合。此外，耦合在到达降落的最后15 m内达到更高的值，对应于悬停阶段和着陆，并且相关性随海平面增加。这种耦合可能有助于提高飞行员的安全性，因为着陆时的耦合越大，撞击时的动能就越小。

结论：将直升机的垂直位移与升沉运动耦合起来似乎是一种将冲击能量最小化的有效策略。有关这种行为背后的理论依据和感知不变性的问题都出现了，并表明有必要进行进一步研究。