Prediction and Assessment of Aircraft/Rotorcraft-Pilot Coupling Phenomena

莱特兄弟对他们第一次和随后的动力飞行的描述表明，他们经历了飞行员引发的俯仰振荡。他们的飞机不稳定，飞行员需要相对较高的预期控制水平才能保持理想的飞行路线。在利物浦莱特项目中，莱特兄弟飞机在飞行员模拟中的飞行重建使这些所谓的飞行员诱发振荡(PIO)变得栩栩如生，我们已经能够解释导致这些振荡的情况，以及潜在的物理机制。与任何现代标准相比，早期的莱特飞机的操纵质量很差，但即使在正常飞行时操纵质量良好的飞机，在适当的情况下也可能被迫进入PIO，正是这种现象的这种阴险特征导致了它仍然神秘，并因此刺激了研究。PIO在第一次动力飞行中的出现是一个信号，表明它们将永远存在于航空发展中。固定翼飞机PIO的臭名昭著的例子，例如YF-16首次飞行期间的侧滚PIO和萨博Grippen在两次演示飞行中的俯仰偏离，往往会因为强烈的公众兴趣和随后的分析而被记住，但同样戏剧性的不稳定发生在旋翼飞机上，可以在非官方的视频中看到，例如V-22在船上着陆时的侧滚PIO和集体/升空PIO，以及随后CH-53在外部负载下坠毁。对这些或类似事件的分析结果没有发表在公开文献中，而且对RPC的特点普遍缺乏了解，这意味着继续发生的风险很高；特别是随着新技术的越来越多地使用，特别是全权限数字飞行控制系统，这是几起固定翼飞机事故的一个促成因素。PIO属于一类被称为飞机/旋翼机-飞行员-耦合(A/RPC)的现象，这一专题是拟议研究的主题。我们研究的目的是发展理论，建立模型并解释有助于APC的物理机制。这一理论将通过基于实际发生的案例研究和重建的飞行员模拟来提供。这项研究将继续探索在新飞机的设计和测试程序中纳入A/RPC考虑的各种选择。

The description by the Wright Brothers of their first and subsequent powered flights suggests that they experienced pitch oscillations of a pilot-induced nature. Their aircraft were unstable and there was a need for a relatively high level of anticipatory control by the pilot to hold a desired flight path. The re-construction of the flights of the Wright Brothers' aircraft in piloted simulation in the Liverpool Wright Project has brought these so called PIOs (pilot-induced-oscillations) to life and we have been able to explain the circumstances that lead to them, and the underlying physical mechanisms. The early Wright aircraft had poor handling qualities, compared with any modern standard, but even aircraft with good handling qualities while in normal flight, can be forced into a PIO given the right circumstances and it is this insidious character of the phenomena that has led to its continuing mystery and consequent stimulus for research. The presence of PIO's in the first ever powered flights was a signal that they would be ever present in the development of aviation. The infamous examples of fixed wing aircraft PIOs, such as the roll PIO during the 'first' flight of the YF-16 and the pitch departure of the Saab Grippen in two demonstration flights, tend to be remembered because of the intense public interest and subsequent analysis but equally dramatic instabilities have occurred on rotorcraft and can be seen on 'unofficial' videos, e.g. roll PIO of a V-22 during shipboard landing and collective/heave PIO and subsequent crash of a CH-53 with external load. Results from the analysis of these, or similar, occurrences have not been published in the open literature and the generally poor understanding of the peculiarities of RPC's means that the risk of continuing occurrence is high; especially with the increasing utilisation of new technologies, particularly full authority digital flight control systems, a contributing factor in several fixed-wing aircraft incidents. PIOs are in a class of phenomena called aircraft/rotorcraft-pilot-couplings (A/RPCs) and this topic is the subject of the proposed research. The intention in our research is to develop theory which 'models' and explains the physical mechanisms that contribute to APCs. The theory will be informed by case studies based on actual occurrences and reconstructed pilot simulations. The research will go on to explore options for including A/RPC considerations within design and testing procedures for new aircraft.