Download or read book Full Scale Crash Test and Finite Element Simulation of a Composite Prototype Helicopter written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: A full-scale crash test of a prototype composite helicopter was performed at the Impact Dynamics Research Facility at NASA Langley Research Center in 1999 to obtain data for validation of a finite element crash simulation. The helicopter was the flight test article built by Sikorsky Aircraft during the Advanced Composite Airframe Program (ACAP). The composite helicopter was designed to meet the stringent Military Standard (MIL-STD-1290A) crashworthiness criteria and was outfitted with two crew and two troop seats and four anthropomorphic dummies. The test was performed at 38-ft/s vertical and 32.5-ft/s horizontal velocity onto a rigid surface. An existing modal-vibration model of the Sikorsky ACAP helicopter was converted into a model suitable for crash simulation. A two-stage modeling approach was implemented and an external user-defined subroutine was developed to represent the complex landing gear response. The crash simulation was executed with a nonlinear, explicit transient dynamic finite element code. Predictions of structural deformation and failure, the sequence of events, and the dynamic response of the airframe structure were generated and the numerical results were correlated with the experimental data to validate the simulation. The test results, the model development, and the test-analysis correlation are described. Jackson, Karen E. and Fasanella, Edwin L. and Boitnott, Richard L. and Lyle, Karen H. Langley Research Center 728-50-10-01
Download or read book Full scale Crash Test and Finite Element Simulation of a Composite Prototype Helicopter written by Karen E. Jackson and published by . This book was released on 2003 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Occupant Responses in a Full Scale Crash Test of the Sikorsky ACAP Helicopter written by and published by . This book was released on 2002 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: A full-scale crash test of the Sikorsky Advanced Composite Airframe Program (ACAP) helicopter was performed in 1999 to generate experimental data for correlation with a crash simulation developed using an explicit nonlinear, transient dynamic finite element code. The airframe was the residual flight test hardware from the ACAP program. For the test, the aircraft was outfitted with two crew and two troop seats, and four anthropomorphic test dummies. While the results of the impact test and crash simulation have been documented fairly extensively in the literature, the focus of this paper is to present the detailed occupant response data obtained from the crash test and to correlate the results with injury prediction models. These injury models include the Dynamic Response Index (DRI), the Head Injury Criteria (HIC), the spinal load requirement defined in FAR Part 27.562(c), and a comparison of the duration and magnitude of the occupant vertical acceleration responses whole-body acceleration tolerance curve.
Download or read book Comparison of Test and Finite Element Analysis for Two Full Scale Helicopter Crash Tests written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2019-01-18 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality. Annett, Martin S. and Horta, Lucas G. Langley Research Center NF1676L-1114
Download or read book Comparison of Test and Finite Element Analysis for Two Full Scale Helicopter Crash Tests written by Martin S. Annett and published by BiblioGov. This book was released on 2013-06 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality.
Download or read book Occupant Responses in a Full Scale Crash Test of the Sikorsky Acap Helicopter written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-19 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: A full-scale crash test of the Sikorsky Advanced Composite Airframe Program (ACAP) helicopter was performed in 1999 to generate experimental data for correlation with a crash simulation developed using an explicit nonlinear, transient dynamic finite element code. The airframe was the residual flight test hardware from the ACAP program. For the test, the aircraft was outfitted with two crew and two troop seats, and four anthropomorphic test dummies. While the results of the impact test and crash simulation have been documented fairly extensively in the literature, the focus of this paper is to present the detailed occupant response data obtained from the crash test and to correlate the results with injury prediction models. These injury models include the Dynamic Response Index (DRI), the Head Injury Criteria (HIC), the spinal load requirement defined in FAR Part 27.562(c), and a comparison of the duration and magnitude of the occupant vertical acceleration responses with the Eiband whole-body acceleration tolerance curve. Jackson, Karen E. and Fasanella, Edwin L. and Boitnott, Richard L. and McEntire, Joseph and Lewis, Alan Langley Research Center NASA/TM-2002-211733, NAS 1.15:211733, ARL-TR-2735, L-18189
Download or read book Smart Textiles for In Situ Monitoring of Composites written by Vladan Koncar and published by Woodhead Publishing. This book was released on 2018-10-29 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smart Textiles for in situ Monitoring of Composites proposes a ‘smart textile’ approach to help solve the problem of real-time monitoring of the structural health of composites. The book combines textiles, composites and structural health monitoring knowledge to present an integrated approach to the deployment of smart textiles to monitor failure modes in composite materials. It introduces the theory of smart textiles for monitoring and measurement applications, describes established and developing techniques and approaches for using smart textiles for in-situ monitoring, and includes different fiber/matrix combinations and hybrid structures that are all presented using academic research and real-world case studies. As smart textiles are fitted with flexible adapted sensors and actuators that detect stress, deformation, temperature changes, light intensity, and other signals from the environment, this book is a timely resource on the topic. Proposes a ‘smart textile’ approach to in situ monitoring of the structural health of composites where the composite structure’s functionalized reinforcement also plays a role Discusses the impact of this technology on different reinforcement materials and matrices Demonstrates, through a review of research and case studies, the implementation of sensing and measurement systems
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1989 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Full Scale Dynamic Crash Test of a CH 21 Helicopter written by W. H. Reed and published by . This book was released on 1963 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Full scale Crash Test of a CH 47C Helicopter written by Claude B. Castle and published by . This book was released on 1976 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Symposium on Vehicle Crashworthiness Including Impact Biomechanics written by Pin Tong and published by . This book was released on 1986 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamic Behavior of Soft and Hard Materials Volume 1 written by R. Velmurugan and published by Springer Nature. This book was released on 2023-12-31 with total page 537 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises the select peer-reviewed proceedings of the 13th International Symposium on Plasticity and Impact Mechanics (IMPLAST) 2022, which was held at Indian Institute of Technology, Madras, to commemorate the 80th birthday of Prof. N K Gupta, IIT, Delhi. It aims to provide a comprehensive and broad-spectrum picture of the state-of-the-art research and development in diverse areas, such as constitutive relations, theories of plasticity, stress waves in solids, earthquake loading, high-speed impact problems, fire and blast loading, structural crashworthiness and failure, mechanics of penetration and perforation, among others. The contents focus on aspects of large deformations and failure of materials, including metals, composites, cellular, geomaterials, or concrete, and structures resulting from quasi-static earthquake, fire, impact, or blast loading. This book is a valuable resource for researchers and professionals working in academia and industry in the areas of mechanical, materials, and aerospace engineering.
Download or read book Full scale Dynamic Crash Test of a Small Observation Type Helicopter written by J. W. Turnbow and published by . This book was released on 1966 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report discusses the results of experimental crash tests of two fully instrumented OH-4A helicopters. The first of these tests, conducted as a crane drop, illustrated the energy absorption capability of the tapered-wall landing gear strut. It further showed that high accelerations may be induced in occupants under level impact conditions of the aircraft in which the design sinking speed for the gear is exceeded. The latter of these tests, conducted from droned flight, indicated that rotor blade impacts with obstacles induced loads into the mast-transmission system which were sufficient to fail the structure at the transmission supports. The crashworthiness of the OH-4A showed an improvement over previous aircraft tested; however, further improvements are definitely possible. This report recommends the means of such improvements and proposes their implementation through appropriate study and test programs. (Author).
Download or read book Verti flite written by and published by . This book was released on 2004 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1993 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1993 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA)
