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The service life of a military ground vehicle is measured in decades and throughout its life it is expected to see several theaters with severe terrain and complex evolving operating conditions. The core of the vehicle, like the chassis and the hull, are often in continuous use, undergoing routine repair, reset, and re-fielding. Other components attached to the hull and chassis have more limited life spans and by design become damaged, worn-out, or outdated and are repaired, replaced, and/or upgraded. New components like armor, weapons, and sensor packages are frequently added to the existing structure for improved mission performance (survivability, lethality, etc.) as threats and strategies change. Designing military vehicles for durability is therefore very challenging and should not end when the product is designed, validated with hardware tests, manufactured, and sold.

A structural damage detection system has been used to sense the propagation of cracks in a metallic flight test specimen on board a Hawk jet trainer. The work has demonstrated that the growth of structural cracks can be successfully and automatically detected on board a fast jet while flying unrestricted flight profiles. The experiment was part of a European collaborative defense program designed to demonstrate a number of diverse structural health monitoring technologies during flight in a military jet environment. This paper focuses on the performance of an acoustic emission detection system that was able to detect the growth of cracks in an alloy cantilever specimen bolted to a structural bulkhead in a pod suspended beneath the aircraft's left hand wing.

Electrification of aircraft is on track to be a future key design principal due to the increasing pressure on the aviation industry to significantly reduce harmful emissions by 2050 and the increased use of electrical equipment. This has led to an increased focus on the research and development of alternative power sources for aircraft, including fuel cells. These alternative power sources could either be used to provide propulsive power or as an Auxiliary Power Unit (APU). Previous studies have considered isolated design cases where a fuel cell system was tailored for their specific application. To accommodate for the large variation between aircraft, this study covers the design of an empirical model, which will be used to size a fuel cell system for any given aircraft based on basic design parameters. The model was constructed utilising aircraft categorisation, fuel cell sizing and balance of plant sub-models.

An essential part of the SHM validation effort is to check the presence and adequacy of the methods required to validate the correct functionality of each SHM task, which can be targeted at detecting structural faults. The ultimate proof of the correct functionality is validation evidence, e.g. crack detection evidence, observed during the operation of the aircraft. However, the occurrences of structural faults such as cracks are infrequent, and hence, years of flight tests might be required to collect validation evidence; small numbers of flights would be only sufficient to prove the system's “fitness for flight” and would be insufficient to prove “fitness for purpose”. Validation evidence can be collected during laboratory tests by inducing faults in structural specimens and examining the SHM detection capability.

UAS (Unmanned aircraft system), widely known to the general public as drones, are comprised of two major system elements: an Unmanned Aircraft (UA) and a Ground Control Station (GCS). UAS have a high mishap rate when compared to manned aircraft. This high mishap rate is one of several barriers to the acceptance of UAS for more widespread usage. Better awareness of the UA real time as well as long term health situation may allow timely condition based maintenance. Vehicle health and usage are two parts of the same solution to improve vehicle safety and lifecycle costs. These can be worked on through the use of two related aircraft management methods, these are: IVHM (Integrated Vehicle Health Management) which combines diagnosis and prognosis methods to help manage aircraft health and maintenance, and FOQA (Flight Operations Quality Assurance) systems which are mainly used to assist in pilot skill quality assurance.

Aircraft as a System of Systems: A Business Process Perspective, written by Sean Barker, FBCS CEng and a former research scientist at BAE Systems in the UK, explains how developing even simple parts like a lever needs several different types of knowledge before moving on to the complications of designing a system. Today's airframers have taken on more of the role of systems integrators, putting the focus on the aircraft as a system-of-many-systems. Whereas an aircraft integrates many different systems into a single design, the system of systems which supports it is built by federating the systems of the different organizations, which were built and run independently of each other. Aircraft as a System of Systems: A Business Process Perspective provides a thorough analysis of how building aircraft taps into a huge pool of knowledge, how its complexity is also reflected in the numerous process links that exchange knowledge between different groups.