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As compared with the maneuvering flight studies for single main rotor helicopters, the corresponding studies for coaxial rotor helicopters are relatively poor. In this paper, the maneuvering flight governing equations for coaxial rotor helicopters is established. By introducing induced velocity interference factor analysis, the coaxial rotor aerodynamic interference can be taken into account. With the combination of coaxial rotor helicopter control features and nonlinear inverse simulation technique, the governing equations for maneuvering flight can be solved so as to determine helicopter control input, control force and moment, and helicopter body attitudes which are needed for performing a specified maneuver. Good results of the sample calculations of level turn and lateral jink maneuvers are obtained and simply analyzed.

The purpose of this study is to test the performance of the designed automatic control system based on the Linear Quadratic Regulator (LQR) and Linear Quadratic Gaussian (LQG) algorithms during landing of the helicopter on the ship deck. This paper is a further development of the series based on Topczewski et al. (2020).

The system consists of two automatic control algorithms based on LQR and the LQG. It is integrated with the ship motion prediction system based on autoregressive algorithm with parameters calculated using Burg’s method. It is assumed that the source of necessary navigation data is integrated Inertial Navigation System with Global Positioning System. Landing of the helicopter on the ship deck is performed in automatic way, based on the preselected procedure. Performance of the control system is analyzed when all necessary navigation data is available for the system and in case when one of the parameters is unavailable during performing the procedure.

In this paper, description of the designed control system developed for performing the approach and landing of the helicopter using selected procedure is presented. Helicopter dynamic model is validated using the manufacturer data and by test pilots, overview is presented. Necessary information about ship motion model is also included. Tests showing mission performance while using LQR and LQG algorithms applied to the control system are presented and analyzed, taking into account both situations when full navigation data is available/unavailable for the control system.

Results of the system performance analyses can be used for selection of the proper control methodology for prospective helicopters autopilots. Furthermore, the system can be used to analyze the mission safety when information about one of the navigation parameters is identified by the navigation system as unavailable or incorrect and therefore unavailable during landing on the ship deck.

In this paper, control system dedicated for the automatic landing of the helicopter on the ship deck, based on two different control algorithms is presented. Influence of lack of information about one of the navigation parameters on the mission performance is analyzed.

The purpose of the work is to carry out analysis of the possibilities and estimation of electric drive efficiency for rotors of helicopter propulsion systems (PS).

Methodology and comprehensive multidisciplinary technology for efficiency estimation of conventional and unconventional architectures PS on rotorcraft system level at preliminary design phase were developed.

Application of the approach allow to carry out analysis of hybrid (based on gas turbine and piston engines) and full electrical PS for superlight-, light- and medium-size helicopters.

It was shown what level of electrical technologies improvement may provide positive effect of the using of hybrid and full electrical helicopter PS of different architectures.

Close matching of helicopter and engine design and calculation aspects, as well as possibilities to use the external (experimental) performances of engine components, whole PS and helicopter aerodynamic performance, are the distinctive features of proposed technology and methodology.

Studies of the hingeless rotor helicopter dynamic stability and control laws are conducted. A new method is given for the calculation of stability and controllability of a helicopter in flight condition with lateral velocity. First, the rotary wing dynamic model considered is the one of flap‐pitch (including the elastic deformation of control system) – torsion coupling. The induced velocity non‐uniform distribution derived from vortex theory is taken into account. Then, according to the established motion model of the helicopter, the effects of induced velocity distribution, flap‐pitch‐torsion coupling and lateral velocity on the stability and controllability of the helicopter are analyzed. Based on the analyses of dynamic stability of the helicopter, the unstable mode and the necessity of installation of stability augmentation system (SAS) are recognized. Finally, the control laws of SAS for helicopter pitching, rolling and yawing motions are presented. After establishing helicopter flight control state equations, the performance analyses and step response simulation for helicopter SAS are carried out.

Children's marginalisation in research limits their opportunities to create meaningful social change. This project explored children's meaningful participation in Participatory Action Research as a tool to empower children as change makers. An adult and child co-researcher collaborated to conduct a literature review on a social issue chosen by the child: helicopter parenting. Highlighting that children and adults have access to different knowledge based on their status in society, the co-researchers wrote about helicopter parenting from three different perspectives: media, psychology and childhood studies. Through a reflection on the research process, the co-researchers offer insight into the impact of mutual relationships, power imbalances, and emotions on children's meaningful participation in research. They also present the value of children's voices in research and research as a learning opportunity for adults and children. Ultimately, the co-researchers aim to challenge readers to reflect on creating more equitable research practices with children to enhance children's opportunities to make change through research.

This paper aims to examine the ethical foundations of Gen Z individuals by studying the impact of helicopter parenting on moral courage and moral disengagement. In addition, this study considers the implications for Millennial generation managers that are likely to be supervising this current generational cohort.

Hypotheses were tested using a two-wave online survey of 215 undergraduate students.

Helicopter parenting was associated with lower levels of moral courage and an elevated propensity to morally disengage in a sample of Gen Z individuals. The impact of helicopter parenting on these moral foundations was mediated by the children’s increased desire for continued parental involvement in their lives.

Similar to the Gen Z students surveyed in this study, many Millennials were raised by helicopter parents, thus, it is likely that they are also prone to moral disengagement and low moral courage. Furthermore, Millennial managers will be managing Gen Z workers. Thus, many companies will need to enhance their efforts in providing Millennial managers with business ethics training aimed at developing moral courage and reducing moral disengagement.

This study examines a previously unidentified antecedent of moral courage and moral disengagement

This study aims to develop a methodology to compare the feasibility of helicopter and seaplane regular transport of passengers towards destinations across a remote regional tourist context, where a lack of road and rail infrastructure make these alternative forms of air transport competitive.

The authors use a modal split model identifying the quota of passengers that potentially could utilize these two types of services, determined on the basis of previous studies on air transport demand. A technical analysis regarding transport supply is performed to identify the predominant features that should characterize helicopter/seaplane performances. An optimization model is applied to identify the routes that could overcome the breakeven point considering each of the two means of transport. The paper also takes into account the importance of each type of service and its influence on flight infrastructure costs.

Helicopter and seaplane services could improve the access for tourists with high values of time. The helicopter transport could capture a market share ranging from 5 to 20 per cent of tourist travel demand (the amphibian seaplane from 1 to 14 per cent). The shuttle services could be profitable especially for those regional origin–destination pairs involving the two major airports and the most UNESCO visited locations such as Agrigento and the Aeolian Archipelago (into the analyzed context of Sicily). The comparison between the two modes of transport shows that the helicopter has best performances and the seaplane has to land/take-off from sea.

The lack of data on the performances of the whole world production of seaplanes and helicopters (such as Russian, Chinese or US old machines) could give a distortion of the result. On the other hand, all mostly used machines in the world at the moment are considered. A survey on the fear of flight and on the choice between the two different forms of air transport could give a more precise result.

From an economic point of view, an operator could choose with more confidence the means of transport to use under different conditions. The activation of passenger services with seaplanes and helicopters can give an impulse to the growth of little operators and to the tourism. So, this study could be a starting point for authorities to plan a regional network of little general aviation airfields and seadromes (located in the great lakes or near the ports) near the major tourist locations. It could make possible to develop a synergic regional commuting traffic involving the seaplane and the helicopter.

Seaplanes and helicopters represent the most important means of transport when poor accessibility conditions and need of ready and fast connections coexist, for example, the commuting between airports and remote regions or downtowns with high tourist or business impact. The activation of passenger services with seaplanes and helicopters can give an impulse to the growth of little operators and to the tourism, consequently to the regional accessibility and economy.

There is a lack of studies involving the comparison between seaplanes and helicopters. This study could represent an important means to analyze the parameters that influence the possibility of activation for this kind of services and to find the factors that influence the feasibility of business with the two different machines. The encouraging performances of the flying boat suggest a future development of an innovative model of medium- and/or high-capacity amphibian seaplane dedicated to passenger transport. It should have take-off/landing performances less dependent on the sea state.

The purpose of this paper is to show the feasibility of constrained model predictive control (MPC) for sophisticated helicopter models which are derived by physical considerations.

Physics‐based modeling is used to create control‐oriented helicopter models. Advanced constrained controllers are designed and tested for these sophisticated models.

The helicopter models are valid and constrained MPC shows considerable promise for robust tracking.

MPCs can be implemented for highly constrained helicopter flights.

A complete process of control‐oriented, physics‐based model development for helicopters followed by MPC design is developed. It is also proved that constrained MPC can be used and implemented online to robustly track discontinuous helicopter trajectories with heterogeneous constraints, even when the models are sophisticated and physics based.

Drawing from life course theory, the purpose of this paper is to investigate the mediating role of family influence on career development (FICD) on the relationship of helicopter-parenting (over-parenting behavior) and US millennials’ work attitudes.

In Study 1 (n=268), confirmatory factor analysis was tested on all scales to derive fit models. Mediation analyses using PROCESS (Preacher and Hayes, 2004) were conducted on Study 1 and Study 2 (n=196) on survey collected data sets.

Capturing life course theorists’ proposition that parental involvement now extends itself through childhood and into millennials’ adulthood, results from both studies indicate helicopter-parenting is related to FICD. Further, for both studies, information support (FICD factor) positively mediates the relationship between helicopter-parenting and, affective commitment and job satisfaction, and negatively mediates the relationship between helicopter-parenting and turnover intentions. Additionally, direct effects on helicopter-parenting on work outcomes were found in both studies.

CEOs and managers seem perplexed on how to manage millennial workers. Understanding the co-occurring positive and negative effects of the millennial-parent relationship on work attitudes can help alleviate this conundrum to create better supervision, retention and engagement of millennial workers.

This study contributes to the sparse empirical literature on millennial’s work attitudes and is the first to provide empirical evidence of the role parents play in shaping millennial’s work attitudes. The findings highlight the concerns CEOs have in managing their millennial workers via their parental relationship and provide insightful management strategies.

The purpose of this paper is to discuss published research in rotorcraft which has taken place in India during the last ten years. The helicopter research is divided into the following parts: health monitoring, smart rotor, design optimization, control, helicopter rotor dynamics, active control of structural response (ACSR) and helicopter design and development. Aspects of health monitoring and smart rotor are discussed in detail. Further work needed and areas for international collaboration are pointed out.

The archival journal papers on helicopter engineering published from India are obtained from databases and are studied and discussed. The contribution of the basic research to the state‐of‐the‐art in helicopter engineering science is brought out.

It is found that strong research capabilities have developed in rotor system health and usage monitoring, rotor blade design optimization, ACSR, composite rotor blades and smart rotor development. Furthermore, rotorcraft modeling and analysis aspects are highly developed with considerable manpower available and being generated in these areas.

Two helicopter projects leading to the “advanced light helicopter” and “light combat helicopter” have been completed by Hindustan Aeronautics Ltd These helicopter programs have benefited from the basic research and also provide platforms for further basic research and deeper industry academic collaborations. The development of well‐trained helicopter engineers is also attractive for international helicopter design and manufacturing companies. The basic research done needs to be further developed for practical and commercial applications.

This is the first comprehensive research on rotorcraft research in India, an important emerging market, manufacturing and sourcing destination for the industry.