Search Results

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.

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.

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.

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.

Fully autonomous systems are seen as the ultimate solution to all manufacturing problems due to their consistent quality and ability to improve rates, but they also have one key disadvantage: Limited equipment versatility. This shortcoming becomes most apparent when trying to apply automation to aircraft final assembly. The variety of jobs is great and would necessitate the development of many unique solutions. Therefore a robotic system designed for one job on one aircraft version might be useless on the next version. Also there are many tight spaces and complex jobs where automation is just not practical, meaning that workers with portable tools will always have some presence in production. The modern smart portable tool as exemplified by the Novator PM Series orbital drill motor is capable of matching the quality and speed of a robotic system while still maintaining the ability to be applicable over a wide variety of jobs.

Designers of future space vehicles envision simplifying the Atmosphere Revitalization (AR) system by combining the functions of trace contaminant (TC) control and carbon dioxide removal into one swing-bed system. Flow rates and bed sizes of the TC and CO2 systems have historically been very different. There is uncertainty about the ability of trace contaminant sorbents to adsorb adequately in a high-flow or short bed length configurations, and to desorb adequately during short vacuum exposures. This paper describes preliminary results of a comparative experimental investigation into adsorbents for trace contaminant control. Ammonia sorbents and low temperature catalysts for CO oxidation are the foci. The data will be useful to designers of AR systems for Constellation. Plans for extended and repeated vacuum exposure of ammonia sorbents are also presented.

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.

This paper reports on the experimental study of carbide and polycrystalline diamond (PCD) drills used for drilling composite/titanium stacks. Materials systems used in this study were multi-directional carbon fiber in an epoxy matrix and titanium 6Al-4V. The drill materials included tungsten carbide (WC; 9%Co ultra fine grain) and polycrystalline diamond (PCD; bimodal grade). Torque and thrust force were measured during the drilling experiments. Tool wear of both drills was periodically examined during the drilling tests using various microscopic techniques such as optical and Scanning Electron Microscope (SEM). Effect of tool materials and process condition on hole quality parameters such as hole diameter, surface roughness, and titanium burrs, were examined. Dissimilar mechanical and thermal properties of the stacks affected the tool life and resulted in the decreased hole quality for both cutting tool materials, although to a differing degree.

{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.”}

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.

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.

Over the last several years, the Federal Aviation Administration (FAA) and the rotorcraft industry have maintained a dialogue regarding minimum airspace requirements at visual flight rule (VFR) heliports. The industry is anxious to locate heliports in strategic downtown city-center areas and wants to size heliport airspace to fit these constrained geometries. The FAA, on the other hand, is concerned that the minimum recommended airspace for VFR heliports or vertiports must be sufficient to ensure safety of operations. Prior FAA studies and testing on this issue have been concerned with a very limited number of obstacles in the vicinity of a specific heliport. No consideration has been given to the psychological effect of a large number of obstacles, or an obstacle-rich environment (ORE), in the vicinity of a heliport or vertiport on pilot performance. This research project is designed to explore and investigate what part obstacles play in pilot performance and perception.

The Sensory Prognostics and Management Systems (SPMS) program sponsored by the Federal Aviation Administration and Boeing developed and evaluated designs to integrate advanced diagnostic and prognostic (i.e., Integrated Vehicle Health Management (IVHM) or Health Management (HM)) capabilities onto commercial airplanes. The objective of the program was to propose an advanced HM system appropriate for legacy and new aircraft and examine the technical requirements and their ramifications on the current infrastructure and regulatory guidance. The program approach was to determine the attractive and feasible HM applications, the technologies that are required to cost effectively implement these applications, the technical and certification challenges, and the system level and business consequences of such a system.

Aviation Data Integration System (ADIS) project explores methods and techniques for integrating heterogeneous aviation data to support aviation problem-solving activity. Aviation problem-solving activities include: engineering troubleshooting, incident and accident investigation, routine flight operations monitoring, flight plan deviation monitoring, safety assessment, maintenance procedure debugging, and training assessment. To provide optimal quality of service, ADIS utilizes distributed intelligent agents including data collection agents, coordinator agents and mediator agents. This paper describes the proposed agent-based architecture of the Aviation Data Integration System (ADIS).

The general aviation community, acting through an informal organization known as the General Aviation Safety Panel (GASP), has sought to develop meaningful recommendations in the area of crashworthiness as it applies to post-crash fires. In support of the GASP efforts the potential fuel volume reduction and weight penalties that might be incurred should crash resistant fuel systems be installed in general aviation fixed-wing aircraft were quantified. A wide range of aircraft sizes and configurations were evaluated and relationships were developed between various aircraft/fuel system parameters to estimate the potential impact that installation of fuel bladder cells might have on aircraft design.

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.

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.

The aerospace ecosystem is a complex system of systems comprising of many stakeholders in exchanging technical, design, development, certification, operational, and maintenance data across the different lifecycle stages of an aircraft from concept, engineering, manufacturing, operations, and maintenance to its disposal. Many standards have been developed to standardize and improve the effectiveness, efficiency, and security of the data transfer processes in the aerospace ecosystem. There are still challenges in data transfer due to the lack of standards in certain areas and lack of awareness and implementation of some standards. G-31 standards committee of SAE International has conducted a study on the available digital data standards in aircraft asset life cycle to understand the current and future landscapes of the needed digital data standards and identify gaps. This technical paper presents the study conducted by the G-31 technical committee.

Unmanned Aircraft Systems (UAS) have been growing over the past few years and will continue to grow at a faster pace in future. UAS faces many challenges in certification, airspace management, operations, supply chain, and maintenance. Blockchain, defined as a distributed ledger technology for the enterprise that features immutability, traceability, automation, data privacy, and security, can help address some of these challenges. However, blockchain also has certain challenges and is still evolving. Hence it is essential to study on how blockchain can help UAS. G-31 technical committee of SAE International responsible for electronic transactions for aerospace has published AIR 7356 [1] entitled Opportunities, Challenges and Requirements for use of Blockchain in Unmanned Aircraft Systems Operating below 400ft above ground level for Commercial Use. This paper is a teaser for AIR 7356 [1] document.