Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1993. / Includes bibliographical references (leaves 79-80). / by Sabine Anne Vermeersch. / M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1994. / Includes bibliographical references (p. 207-217). / by Ronald L. Spangler, Jr. / Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1992. / Includes bibliographical references (leaves 112-113). / by Olivier Etchevers. / M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1989. / Includes bibliographical references (leaves 89-90). / by Judith Ellen Pinsley. / M.S.

Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 103-106). / The runway configuration is a key driver of airport capacity at any time. Several factors, such as wind speed, wind direction, visibility, traffic demand, air traffic controller workload, and the coordination of flows with neighboring airports influence the selection of the runway configuration. This paper identifies a discrete-choice model of the configuration selection process from empirical data. The model reflects the importance of various factors in terms of a utility function. Given the weather, traffic demand and the current runway configuration, the model provides a probabilistic forecast of the runway configuration at the next 15-minute interval. This prediction is then extended to obtain the probabilistic forecast of runway configuration on time horizons up to 6 hours. Case studies for Newark (EWR), John F. Kennedy (JFK), LaGuardia (LGA), and San-Francisco (SFO) airports are completed with this approach, first by assuming perfect knowledge of future weather and demand, and then using the Terminal Aerodrome Forecasts (TAFs). The results show that given the actual traffic demand and weather conditions 3 hours in advance, the models predict the correct runway configuration at EWR, JFK, LGA, and SFO with accuracies 79.5%, 63.8%, 81.3% and 82.8% respectively. Given the forecast weather and scheduled demand 3 hours in advance, the models predict the correct runway configuration at EWR, LGA, and SFO with accuracies 78.9%, 78.9% and 80.8% respectively. Finally, the discrete-choice method is applied to the entire New York Metroplex using two different methodologies and is shown to predict the Metroplex configuration with accuracies of 69.0% on a 3 hour prediction horizon. / by Jacob Bryan Avery. / S.M.

Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics. Thesis. 1970. M.S. / MICROFICHE COPY ALSO AVAILABLE IN AERO LIBRARY. / Bibliography: leaf 94. / M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1989. / Includes bibliographical references (leaves 113-114). / by Timothy E. McQuade. / M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2011. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 197-221). / Carbon nanotubes (CNTs) are a potential new component to be incorporated into existing aerospace structural composites for multi-functional (mechanical, electrical, thermal, etc.) property enhancement and tailoring. Traditional advanced fiber reinforced polymer composites are used for aerospace vehicles due to their high mass-specific properties. Still, improvements are desired including non-mechanical aspects, e.g., higher electrical conductivity is required for shielding layers against electromagnetic (EM) waves and lightning strike, and tailored thermal conductivity is desired for heat management. Currently, effective use of CNTs is limited in macroscopic materials due to numerous issues including difficulties in processing; favorable CNT properties have not translated straightforwardly into macroscopic property enhancement. Factors that cause such scaling and compositing effects include CNT quality, morphology (length, entanglement, alignment, etc.), and CNT-medium and inter-CNT boundary properties. Evaluation of these factors through process-structure-property relations has been difficult due to inconsistency and poor quantification of CNT composite morphology. In this work, a complete characterization of consistent CNT-polymer composite samples with controlled CNT morphology was acquired for the first time. Aligned CNT polymer nanocomposites (A-CNT-PNCs) were fabricated with multi-walled carbon nanotubes (MWNTs) with varying volume fraction (VCNT) between 1-20% embedded in an aerospace-grade epoxy. A-CNTPNC surfaces were controlled to nano-scale roughness for effective CNT-electrode contact, and interface boundary effects were eliminated using unique test techniques. Benchmark electrical and thermal property measurements of A-CNT-PNCs were obtained using complementary bulk and local measurement techniques, with clear structure-property relations due to the controlled, quantified, and non-isotropic CNT morphology. The data were interpreted using both analytical and numerical models to evaluate the effects of the above critical scaling factors, particularly interface properties at CNT-polymer and inter-CNT contacts. Electrical conductivities were measured to have a linear increase with VCNT, resulting in ~104 S/m (axial) and ~102 S/m (transverse) with -20% VCNT, much higher than previously measured data of any CNT-thermoset PNCs in the literature. Meanwhile, the extracted per-CNT resistance, 107 Q, is comparable to individually measured values in the literature, confirming that scaling and compositing effects can be minimized. Thermal conductivities, both axial and transverse, were experimentally observed to rapidly increase at a certain high VCNT (-10%). This experimental observation is novel, as CNT-PNCs have never been fabricated and tested with such high VCNT or with non-isotropy from CNT alignment. When studied analytically and numerically, this non-linear behavior is partially explained by thermal boundary resistances, mainly at CNTpolymer contacts (quantified as ~10-8 m2K/W). Although A-CNT-PNC thermal conductivity is still low in the VCNT range tested (-4 W/mK with 16% VCNT), the rapid increase trend suggests the potential for further enhancement of thermal conduction. These experimental data sets demonstrate that individual CNT properties can be scaled when morphology is controlled, suggesting a specific means to further composite property improvement: greater CNT alignment to avoid inter-CNT contacts for electrical transport, and CNT-polymer and inter-CNT interface enhancement to reduce resistances for thermal transport. Based on the above, a model macroscopic nano-engineered composite (CNTs, fibers, and polymer) was fabricated through direct growth of radially aligned CNTs on 11 pm-diameter alumina fibers in a woven cloth and hand lay-up. Measured laminate electrical and thermal properties (-1 W/mK and -100 S/m) were consistent with the A-CNT-PNC study, and confirmed the CNT-implemented composite's potential for applications such as electromagnetic interference shielding. The benchmark experimental data and findings and multi-scale framework established in this work can contribute to optimal use of CNTs and other conductive nano-particles in macroscopic materials for numerous applications: damage sensing in airplane structures, electrical interconnects, thermal interface materials, and power electrode or storage materials. Future work includes further understanding of transport limiting factors using improved models that can accommodate more complex CNT geometries and associated boundary effects, and tailoring of macroscopic CNT composites by extending CNT-growth substrates and matrices for a variety of applications. / by Namiko Yamamoto. / Ph.D.

Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2014. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 175-178). / The current downward trend in funding for U.S. defense systems seems to be on a collision course with the state of the practice in systems engineering, which typically results in the increased pace and scale of capabilities and resultantly increased cost of complex national defense systems. Recent advances in the state of the art in systems engineering methodology can be leveraged to address this growing challenge. The present work leverages advanced constructs and methods for early-phase conceptual design of complex systems, when committed costs are still low and management influence is still high. First, a literature review is presented of the topics relevant to this work, including approaches to the design of affordable systems, assumptions and methods of exploratory modeling, and enabling techniques to help mitigate the computational challenges involved. The types, purposes, and limits of early-phase, exploratory models are then elucidated. The RSC-based Method for Affordable Concept Selection (RMACS) is described, which comprises nine processes in the three main thrusts of information gathering, evaluation, and analysis. The method is then applied to a naval ship case example, described as the Next-Generation Combat Ship, with representational information outputs and discussions of affordability with respect to each process. The ninth process, Multi-Era Analysis (MERA), is introduced and explicated, including required and optional informational components, temporal and change-related considerations, required and optional activities involved, and the potential types of outputs from the process. The MERA process is then applied to a naval ship case example similar to that of the RMACS application, but with discrete change options added to enable a tradespace network. The seven activities of the MERA process are demonstrated, with the salient outputs of each given and discussed. Additional thoughts are presented on MERA and RMACS, and 8 distinct areas are identified for further research in the MERA process, along with a brief description of the directions that such research might take. It is concluded that the affordability of complex systems can be better enabled through a conceptual design method that incorporates MERA as well as metrics such as Multi-Attribute Expense, Max Expense, and Expense Stability. It is also found that affordability of changeable systems can be better enabled through the use of existing path-planning algorithms in efficient evaluation and analysis of long-term strategies. Finally, it is found that MERA enables the identification and analysis of path-dependent considerations related to designs, epochs, strategies, and change options, in many possible futures. / by Michael Andrew Schaffner. / S.M.

Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1962. / Vita. / Includes bibliographical references (leaves 216-223). / by Eugene John Brunelle, Jr. / Sc.D.