Operational criteria for battlefield vehicles

textModern military ground vehicles are no longer able to respond effectively to the rapidly changing mission requirements of modern military conflicts. Military vehicle architectures, which utilize passive suspension components and traditional drivetrain/steering systems, do not provide the operational flexibility to meet the demands of the operator. Advances in intelligent actuation technology allow for the development of a new vehicle architecture - the Intelligent Corner Vehicle (ICV). The ICV utilizes intelligent actuator technology to actively control the four degrees of freedom of each wheel of the vehicle - drive, camber, steering, and suspension. The utilization of intelligent actuation requires the characterization of the motions and behavior of the tire and the vehicle chassis in order to effectively apply the tire to the road surface - the development of vehicle performance criteria. A brief review of the state of wheeled military systems is presented. Many modern military vehicles were designed to improve protection at the expense of mobility - a process that has had negative effects on vehicle capability. An overview of the pneumatic tire used for wheeled vehicles is presented, highlighting the nonlinearities of tire behavior. The complexity of tire force generation drives the need for the application of intelligent actuation. Traditional actuation of wheel motion is presented along with a variety of current efforts to apply intelligent actuation to individual degrees of freedom of the tire. These efforts can be shown to improve vehicle performance, but intelligent actuation must be applied to all aspects of tire motion, requiring the use of the ICV architecture and the generation of performance criteria by which the complex motion of the vehicle may be evaluated. The Robotics Research Group has a history of developing and evaluating performance criteria for complex dynamic systems. and review of performance criteria developed for serial chain robotics is presented. These criteria address task independent actuator motion in addition to actuator ranges and limits, and their application to the ICV is discussed. A brief overview of several important concepts of classical vehicle dynamics are presented. The application of criteria derived from these concepts to the ICV architecture is discussed. This report presents the complexities of tire behavior and vehicle motion, the need for alternative architectures (the ICV), and a variety of performance criteria required to evaluate vehicle motion in real time. Criteria that are presented are summarized along with their definition and physical meaning. Future work for the development of the ICV involves the generation of a vehicle model for evaluating the application and range values of the presented criteria.Mechanical Engineerin

Applications of advanced transport aircraft in developing countries

Four representative market scenarios were studied to evaluate the relative performance of air-and surface-based transportation systems in meeting the needs of two developing contries, Brazil and Indonesia, which were selected for detailed case studies. The market scenarios were: remote mining, low-density transport, tropical forestry, and large cargo aircraft serving processing centers in resource-rich, remote areas. The long-term potential of various aircraft types, together with fleet requirements and necessary technology advances, is determined for each application

AN ATLAS FOR NAVIGATING THE INNOVATION ECOSYSTEM: HYBRID AIRSHIPS AS A USE CASE TO ENGAGE THE COMMERCIAL SECTOR

The Chief of Naval Operations and Commandant of the Marine Corps have stated the need to streamline innovation practices for faster adoption of emerging technologies to support force design initiatives. However, the Department of Defense (DOD) innovation ecosystem is difficult to navigate. This research develops an atlas to guide interaction and engagement for DOD personnel to navigate the innovation ecosystem while assessing commercially-developed, large-capacity transportation platforms. Using hybrid airships as the use case, the authors employed two research methods while developing the atlas: 1) technology progress and cost modeling and 2) market analysis through research and interviews with industry leaders. The results confirm that early DOD engagement with commercial partners can positively influence long-term procurement options. The authors believe that the atlas can guide timely and productive engagement with the commercial sector for the sustainable development of large-capacity platforms, but must have a framework that protects commercial intellectual property. We recommend that the DOD utilize the atlas to explore how commercial markets will affect future hybrid airship development, while creating a more complete picture of the function and utility of these versatile platforms.Outstanding ThesisCaptain, United States Marine CorpsCaptain, United States Marine CorpsApproved for public release. Distribution is unlimited

Aeronautical engineering: A continuing bibliography, supplement 122

This bibliography lists 303 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1980

Future regional transport aircraft market, constraints, and technology stimuli

This report provides updated information on the current market and operating environment and identifies interlinking technical possibilities for competitive future commuter-type transport aircraft. The conclusions on the market and operating environment indicate that the regional airlines are moving toward more modern and effective fleets with greater passenger capacity and comfort, reduced noise levels, increased speed, and longer range. This direction leads to a nearly 'seamless' service and continued code-sharing agreements with the major carriers. Whereas the benefits from individual technologies may be small, the overall integration in existing and new aircraft designs can produce improvements in direct operating cost and competitiveness. Production costs are identified as being equally important as pure technical advances

Transitioning The U.S. Air Transportation System To Higher Fuel Costs

The air transportation system enables economic growth and provides significant social benefits. Future increases and volatility in oil prices, as well as climate change policies, are likely to increase the effective cost of fuel. We investigate the expected impacts of higher fuel costs on the U.S. domestic air transportation system and discuss policy options to reduce negative economic and social effects. The 2004-08 fuel price surge is used as a historical case study. A stochastic simulation model is developed using price elasticity of demand assumptions and flight leg fuel burn estimates to understand the impacts of higher fuel costs. It was found that a 50% increase in fuel prices is expected to result in a 12% reduction in ASMs if all cost increases pass through to passengers. System revenues are expected to decrease marginally for fuel price increases up to 50%, but higher increases may result in significant revenue reductions. Small airports are expected to experience relatively larger decreases and greater volatility in traffic. Older aircraft, flying sectors significantly below their optimal fuel efficiency range, are expected to experience the greatest reductions in capacity. An airline case study demonstrates that a regional carrier may be less sensitive to increased fuel prices than other business models. Policy options to maintain small community access, to manage airport traffic volatility, and to improve fleet fuel efficiency are discussed. To transition the U.S. air transportation system to higher fuel costs, stakeholder action will be required.MIT Partnership for AiR Transportation Noise & Emissions Reduction (PARTNER) provided access to the Piano-X aircraft performance database. The Transportation Research Board’s (TRB) Airport Cooperative Research Program (ACRP) supported this work through the Graduate Research Award Program on Public-Sector Aviation Issues

Understanding Algorithm Performance on an Oversubscribed Scheduling Application

The best performing algorithms for a particular oversubscribed scheduling application, Air Force Satellite Control Network (AFSCN) scheduling, appear to have little in common. Yet, through careful experimentation and modeling of performance in real problem instances, we can relate characteristics of the best algorithms to characteristics of the application. In particular, we find that plateaus dominate the search spaces (thus favoring algorithms that make larger changes to solutions) and that some randomization in exploration is critical to good performance (due to the lack of gradient information on the plateaus). Based on our explanations of algorithm performance, we develop a new algorithm that combines characteristics of the best performers; the new algorithms performance is better than the previous best. We show how hypothesis driven experimentation and search modeling can both explain algorithm performance and motivate the design of a new algorithm

Air Mobility Command\u27s EN Route Support Infrastructure: A Construct of Aircraft Type and Geographic Location Utilized to Assess En Route Aircraft Logistics Support

The ability of the United States Armed Forces to maintain a global presence and rapidly project military power anywhere in the world are key factors in preserving our freedom. To accomplish the demanding task of global reach support, Air Mobility Command employs an en route support infrastructure. These en route locations provide varying levels of command, control, and communications (C3), logistics support, and aerial port functions. The goal of the en route is to minimize delays for AMC mission aircraft. However, these en route locations comprise a small percentage of the locations that AMC aircraft visit. Given the critical demand for rapid air mobility, potential impact of mission delays or cancellations, and the substantial investment of taxpayer dollars, AMC must provide logistical support to off-station aircraft in the most effective manner possible. This research examined a 5-year historical summary of AMC’s logistical support process. The resulting data was used to perform a statistical analysis of AMC off-station aircraft logistic support records for AMC’s six primary aircraft fleets (C-5, C-17, C-141, C-130, KC-10, & KC-135). The calculated average not mission capable (NMC) time was used to compare overseas en route and non en route locations to assess AMC’s en route infrastructure’s effectiveness in reducing mission delays due to aircraft maintenance problems. Effectiveness, in the context of this research, was measured in terms of a lower or shorter average NMC time, equating to reduced mission delays.The initial data analysis on OCONUS en route and non en route locations provided a macro level assessment based on location only. A closer investigation on each of the six primary AMC aircraft fleets returned varying results in terms of reduced averaged NMC time. To determine if a significant difference existed between data groups, parametric and nonparametric statistical testing methods were used. All data groups were tested for normal distributions using histograms and goodness-of-fit tests. Each of the data set had non-normal or non-lognormal distribution and unequal variances based on F-test results. Mann-Whitney (Wilcoxon) tests were used to determine significant differences between the ranked sums and unpaired two-sample Student’s t-tests assuming unequal variances were also applied to test for differences in population means. The results of this study indicate that the OCONUS en route infrastructure is effective in reducing average NMC time as compared to OCONUS non en route locations, except in the case of the KC-135 fleet. Overall, en route locations appear to reduce average NMC time by more than 17 hours. Results of the aircraft fleet comparisons reveal significant reductions in NMC time for the C-5, C-17, C-141, and KC-10 fleets. The C-130 fleet appeared to achieve a slight reduction in average NMC time. In the case of the KC-135, the en route average NMC time was nearly one hour higher than non en route locations. The findings of this study could be further evaluated by the suggested future research topics