Flight test

Abstract: To investigate and develop unmanned vehicle systems technologies for autonomous multiagent mission platforms, we are using an indoor multivehicle testbed called real-time indoor autonomous vehicle test environment (RAVEN) to study long-duration multivehicle missions in a controlled environment. Normally, demonstrations of multivehicle coordination and control technologies require that multiple human operators simultaneously manage flight hardware, navigation, control, and vehicle tasking. However, RAVEN simplifies all of these issues to allow researchers to focus, if desired, on the algorithms associated with high-level tasks. Alternatively, RAVEN provides a facility for testing low-level control algorithms on both fixed- and rotary-wing aerial platforms. RAVEN is also being used to analyze and implement techniques for embedding the fleet and vehicle health state (for instance, vehicle failures, refueling, and maintenance) into UAV mission planning. These characteristics facilitate the rapid prototyping of new vehicle configurations and algorithms without requiring a redesign of the vehicle hardware. This article describes the main components and architecture of RAVEN and presents recent flight test results illustrating the applications discussed above.

Abstract: : The document is published in support of Military Specification MIL-F-8785B, 'Flying Qualities of Piloted Airplanes.' It was compiled after an extensive literature review and many meetings and discussions with personnel from essentially all concerned civilian and governmental organizations. The primary purpose is to explain the concept and philosophy underlying MIL-F-8785B and to present some of the data and arguments upon which the requirements were based. A secondary purpose is to present what are believed to be the important governing variables in the field of flying qualities and to define their significance and relationship to each other. The significance of such mission- oriented factors as airplane class, flight phase, flight condition, loading and configuration is discussed, as is the treatment of failure states. The document should also, to a degree, serve as a summary of the state of the flying qualities art as determined from operational experience, flight test, experiment, analysis and theory.

Abstract: Presenting proven methods, practical guidelines, and real-world flight-test results for a wide range of state-of-the-art flight vehicles, "Aircraft and Rotorcraft System Identification, Second Edition" addresses the entire process of aircraft and rotorcraft system identification from instrumentation and flight testing to model determination, validation, and application of the results. In this highly anticipated second edition, authors Tischler and Remple have added dedicated in-depth chapters presenting extended model structures and identification results for large flexible transport aircraft, and the detailed methodology to develop a continuous full flight envelope simulation model from individual system identification models and trim test data. Topics Discussed include: Frequency-response methods that are especially well suited for system identification of flight vehicle models from flight-test data; specific guidelines for flight testing, data analysis, and the proper selection of model structure complexity; and emphasis on the importance of physical insight in model development and applications. Special features: student version of CIFER[registered] with updated graphical user interface using MATLAB[registered]; numerous flight-test results for both manned and unmanned vehicles illustrating the wide-ranging roles of system identification, including the analysis of flight mechanics, feedback control, handling qualities, subsystem dynamics, structural analysis, higher-order models for aircraft and rotorcraft, and simulation; and, extensive problem sets at the end of each chapter, with many exercises based on flight-test data provided for the XV-15 in hover and cruise giving the reader hands-on real-world experience with system identification methods and interpretation of the results.

Abstract: A design methodology based on the principles of system analysis was used to design a noise abatement approach procedure for Louisville International Airport. In a flight demonstration test, the procedure was shown to reduce the A-weighted peak noise level at seven locations along the flight path by 3.9 to 6.5 dBA, and to reduce the fuel consumed during approach by 400 to 500 lb (181 to 227 kg). The noise reduction is significant given that a 3-dB difference represents a 50% reduction in acoustic energy and is noticeable to the human ear, and the 7% reduction in the size of the 50 day night average noise level (DNL) contour that would result if all aircraft were to perform the procedure. The fuel saving is also significant, given the financial benefit to airlines and the accompanying reduction in gaseous and particulate emissions. Although the analysis of aircraft performance data showed how pilot delay, in combination with auto-throttle and flight management system logic, can result in deviations from the desired trajectory, the results confirm that near-term implementation of this advanced noise abatement procedure is possible. The results also provide ample motivation for proposed pilot cueing solutions and low-noise guidance features in flight management systems.