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Health Ready Components are essential to unlocking the potential of Integrated Vehicle Health Management (IVHM) as it relates to real-time diagnosis and prognosis in order to achieve lower maintenance costs, greater asset availability, reliability and safety. IVHM results in reduced maintenance costs by providing more accurate fault isolation and repair guidance. IVHM results in greater asset availability, reliability and safety by recommending preventative maintenance and by identifying anomalous behavior indicative of degraded functionality prior to detection of the fault by other detection mechanisms. The cost, complexity and effectiveness of the IVHM system design, deployment and support depend, to a great extent, on the degree to which components and subsystems provide the run-time data needed by IVHM and the design time semantic data to allow IVHM to interpret those messages.

In the aircraft design process there are the occasional bolted joints with opposing surfaces that are not parallel to each other. This can necessitate manufacturing to machine a spot face into the structural surfaces for the bolt head and nut to seat on. Typically this process is done manually by two workers with all process verification being done visually. Additionally, the nature of airplane structure often requires one worker to be inside a confined space to monitor the process. With this in mind, a tool was requested to reduce the number of workers required, remove workers from confined spaces and ensure a robust method for process validation. The critical technology that would have to be developed was a device that could fix itself into an existing hole, measure the surface of which the hole exited and then machine a spot face into that surface to a specific calculated depth. The device would only require a single operator to install and start the machine in a given hole.

Validation is a critical component of model-based design (MBD). Without it, regardless of the level of model verification, neither the accuracy nor the domain of applicability of the models is known. Thus, it is risky to base design decisions on the predictions of unvalidated models. The Integrated Vehicle Energy Technology (INVENT) program is planning a series of hardware experiments that will be used to validate a large set of unit-, subsystem-, and system-level models. Although validating such a large number of interacting models is a large task, it provides an excellent opportunity to test the limits of MBD.

The diverse and complex requirements of next-generation energy optimized aircraft (EOA) demand detailed transient and dynamic model-based design (MBD) to ensure the proper operation of numerous interconnected and interacting subsystems across multiple disciplines. In support of the U.S. Air Force's Integrated Vehicle Energy Technology (INVENT) program, several MBD-derived software tools, including models of EOA technologies, have been developed. To validate these models and demonstrate the performance of EOA technologies, a series of Integrated Ground Demonstration (IGD) hardware tests are planned. Several of the numerous EOA software tools and MBD-based processes have been updated and adapted to support this activity.

The diverse and complex requirements of next-generation energy optimized aircraft (EOA) demand detailed transient and dynamic model-based design (MBD) to ensure the proper operation of numerous interconnected and interacting subsystems. In support of the U.S. Air Force's Integrated Vehicle Energy Technology (INVENT) program, several software tools have been developed and are in use that aid in the efficient MBD of next-generation EOA. Among these are subsystem model libraries, automated subsystem model verification test scripts, a distributed co-simulation application, and tools for system configuration, EOA mission building, data logging, plotting, post-processing, and visualization, and energy flow analysis. Herein, each of these tools is described. A detailed discussion of each tool's functionality and its benefits with respect to the goal of achieving successful integrated system simulations in support of MBD of EOA is given.

Increasing the automation in a flight deck has not always led to benefits to the pilot; instead it is often found that inappropriate implementation of automation can cause a variety of issues including loss of situation awareness, poorer performance, and a perceived increase in workload. It is important to determine in what context a pilot might benefit the most from the inclusion of automation and then to determine the appropriate level at which that automation is implemented. The objective of this study was to evaluate what level of automation is most appropriate for supporting the pilots in the performance of non-normal event resolution tasks. Pilots were given a series of scenarios where the level of automation for performing tasks was varied from no automation to full automation. A related objective was to determine whether the use of a voice interface is effective in providing sufficient feedback to support the pilots' situation awareness.

Parallel kinematic mechanisms (PKMs) offer advantages of high stiffness to mass ratios, greater potential for accuracy and repeatability, and lower cost when compared to traditional assembly machines. Because of this, there is a strong interest in using PKMs for aerospace assembly and joining operations. This paper looks at the calibration of a prototype Gantry TAU robot by extending the higher-order implicit loop calibration techniques developed for serial link mechanisms to parallel link mechanisms. The kinematic model is based on the geometric model proposed by Dressler et al., augmented with a cubic spline error model of the motion errors for each of the three translation actuators resulting in 185 parameters. Measurements are taken with a 6-DOF laser tracker, and the kinematic parameters are solved as the maximum likelihood parameter estimate.

In-flight icing occurs when supercooled water droplets suspended in the atmosphere impinge on cold aircraft surfaces. Thin layers of accreted ice significantly increase aerodynamic drag while thick layers of ice severely alter the aerodynamics of control surfaces and lift. Chunks of ice can break away from the airframe and cowlings and be ingested into engines causing considerable damage. Developing durable surfaces that prevent the nucleation of supercooled water or reduce ice adhesion to a point where airstream shear forces can remove it would allow the design of a more robust, energy efficient deicing/anti-icing system for aircraft and other applications. In this work, a simulations based framework is developed to predict anti-icing performance of various nanocomposite coatings under the in-flight environment.

This paper describes a framework for developing an Integrated Electrical Power System (EPS) Health Management System. The framework is based on the perspective that health management, unlike other capabilities, is not a self-contained, stand-alone system, but is rather an integral part of every aircraft subsystem, system, and the entire platform. Ultimately, the objective is to improve the entire maintenance, logistics and fleet operations support processes. This perspective requires a new mindset when applying systems engineering design principles. The paper provides an overview description of the framework, the potential benefits of the approach and some critical design and implementation issues based on current development efforts.

Structural Health Management (SHM) and its related technologies offer the combined benefits of reducing maintenance costs while maintaining or improving structural design performance. SHM implementation for in-service aerospace platforms requires an approach to quantify how each application can provide benefits. A clear understanding from a benefits perspective provides insight to optimize SHM system design. The focus of this paper will be to describe the key aspects of SHM design from a large scale systems integration perspective. This will be accomplished by a brief overview of SHM from a design and integration perspective, followed by a discussion of SHM derived requirements in the context of example applications. Detailed assessments of a particular application often uncover very stringent requirements to meet existing design, operational performance, qualification, and certification criteria.

{Next-generation network enabled (eEnabled) airplanes will digitally communicate with ground systems continuously at airport, for collection, distribution and loading of airplane data and software parts. Wireless technologies further bring the opportunity of pervasive connection with eEnabled airplane anywhere at airports. However, safety critical airplane information assets mandate secure solutions for eEnabled airplane applications. In this paper, we address the issue of securing wireless eEnabled airplane applications at airports for reliable and safe airplane operation. We identify the special challenges and present research results by comparing the state-of-the-art technologies and proposing the strategy of “defense in depth.”}