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A new control strategy for wheel slip control, considering the complete dynamics of the electro-hydraulic brake (EHB) system, is developed and experimentally validated in Cranfield University's HiL system. The control system is based on closed loop shaping Youla-parameterization method. The plant model is linearized about the nominal operating point, a Youla parameter is defined for all stabilizing feedback controller and control performance is achieved by employing closed loop shaping technique. The stability and performance of the controller are investigated in frequency and time domain, and verified by experiments using real EHB smart actuator fitted into the HiL system with driver in the loop.

The successful completion of aerospace projects usually involves the bringing together of many different specialist skills. The need for the engineer to become multidisciplined is today's reality, but this is becoming increasingly harder to achieve naturally in the working place. Recent industrial drives towards concurrent engineering have revealed a need for just this type of engineer. The 3 year part-time MSc course in Aircraft Engineering was designed to address these needs and was launched with the first intakes of delegates in 1995. The course is modular and students are encouraged to “mix” disciplines, combining topics such as avionics and structural analysis. The course has created skilled specialists and engineering leaders for the future, with improved technical ability and career potential, albeit at the cost of hard work! The course consists of 3 elements, namely:- Lecture courses held in one-week blocks, over the 3 year period. An individual piece of research.

This paper describes a computer code for conceptual design of mission optimized twin-turboprop Commuter or Regional aircraft. Optimum configurations and flight profiles of such aircraft are determined by coupling this code to an optimization code based on Simulated Annealing. As an example, minimum DOC configurations were determined for 50-seat Regional aircraft for operation over three stage lengths. The DOC per seat-nm and DOC per trip of the optimum aircraft were found to be comparable or significantly (8 to 17 %) lower than the corresponding values for five contemporary 40 to 50 seater aircraft for short stage lengths.

A multivariate optimisation code has been modified to represent the application of laminar flow to transport aircraft. This has subsequently been used to obtain optimised configurations for conventional and laminar flow designs. Results are presented, demonstrating the economic benefits of introducing laminar flow technologies to subsonic transport aircraft, with passenger payloads in the 107-517 range. These benefits are seen to improve by a factor of between two and three when the designs are optimised to take maximum advantage of the laminar flow. Sensitivity studies were conducted to investigate the impact of the assumptions used within the project studies on the optimum configurations and operating economics.

An accurate simulation of a ground vehicle interacting with a crosswind gust can be achieved by using a moving model mounted on a track such that it can traverse the working section of a conventional atmospheric boundary layer wind tunnel. This paper will briefly describe the facility that is being developed at Cranfield University and detail comparisons between static and dynamic data from tests on three basic model configurations. Under the same nominal wind input, data from static tests compares well with that from dynamic tests at yaw angles below 15°. At higher yaw angles, after the onset of “large scale” separation, the dynamic values of the forces and moments become larger than the static values.

Different feasibility studies have been carried out over several years at the Royal Military College of Science (RMCS) into medium military airlifters aimed, in essence at replacing the C-130. The studies, each occupying a nominal 1,500 manhours (but probably 50% more) formed part of the final year of the AeroMechanical B.Eng degree at RMCS. The intention of this paper is to draw together their major findings and deals predominantly with the topics of: cargo hold sizing and body aerodynamics, powerplant selection, weight and performance.

Upon their arrival, Unmanned Autonomous Systems (UAS) brought with them many benefits for those involved in a military campaign. They can use such systems to reconnoiter dangerous areas, provide 24-hr aerial security surveillance for force protection purposes or even attack enemy targets all the while avoiding friendly human losses in the process. Unfortunately, these platforms also carry the inherent risk of being built on innately vulnerable cybernetic systems. From software which can be tampered with to either steal data, damage or even outright steal the aircraft, to the data networks used for communications which can be jammed or even eavesdropped on to gain access to sensible information. All this has the potential to turn the benefits of UAS into liabilities and although the last decade has seen great advances in the development of protection and countermeasures against the described threats and beyond the risk still endures.

Unique and groundbreaking—this highly-anticipated book addresses both basic and advanced concepts critical for the understanding and support of the developing field of Integrated Vehicle Health Management (IVHM). From an initial idea by the SAE IVHM Steering Group, collaboratively written by experts from academia, research and industry, the thirteen chapters within this book represent the collective voice of the most qualified authorities in the field. Highlights of the book include: -a single definition and taxonomy of IVHM, as well as basic principles -the identification of how and where IVHM should be implemented -the commercial value of IVHM -vehicle health management systems engineering -algorithms and their impact on IVHM -IVHM future directions and issues -Case study on IHUMS This book serves as the perfect introduction to IVHM for engineers, executives, academic instructors, and students.