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This "TR" is actually a textbook on atmospheric entry for several classes at AFIT. It teaches from an analytical perspective, with finding closed-form solutions being the preferred approach. The over-arching goal is to instill and understand how "families of solutions" behave as well as the general trends, trade-offs, and the nature of atmospheric entry before picking point designs to study in detail. By thoroughly understanding the classic analytic analyses first, we can better use the computer to solve the hard problems. The book's approach is to use easily visualized variables to solve the analytical problems first and keep them (more-or-less) consistent as we move to the computer. This is a "back to the basics" approach for a new generation of students who've become more comfortable with numerical solutions than analytical ones. The pages are loaded with equations because the details of many of the derivations are included. This book pulls together many classical analyses and presents them in a consistent notation for the first time. It provides a convenient starting point for an analytical understanding of atmospheric entry, with plenty of references to those original works. It ties together results that were originally published years apart by different authors. And, peppered throughout, you'll find some new approaches and results., The original document contains color images.

Briefing charts from presentation on the progress in the development of the U.S. Air Force UAV Global Hawk., See also ADM001676. Presented at UAV 2002 Conference & Exhibition held in Paris, France on 11-14 Jun 2002. The original document contains color images. Report contains briefing charts only.

In this investigation of periodic orbits about asteroids rotating in free space, oscillatory orbits about equilibrium points as well as those orbits encircling the body were found. While a method was derived for finding orbits of all inclinations, only equatorial orbits are presented. The major emphasis is on stable, periodic orbits, but certain unstable orbits are presented where appropriate. The analysis assumed that asteroids could be represented by triaxial ellipsoidal bodies rotating about their major axis of inertia. Hamilton's canonical equations were derived to describe the dynamics. An algorithm was then developed and used to solve the equations of motion in such a way as to find closed, periodic orbits. Keywords: equilibrium points; Periodic orbits; Triaxial ellipsoids. (Theses)

A new system for autonomous satellite navigation is developed and investigated. Unlike many previous studies, however, this system is not limited to the determination of an Earth satellite's current position. By using a two- step technique combined with a general perturbations model, this method allows the air-drag effect on the orbit to be estimated and applied to a future position prediction. Simulations using existing hardware have demonstrated that the algorithm presented is capable of current position estimates of sub- kilometer accuracy. Prediction precisions rival those of ground-based facilities: 8-12 kilometers two weeks in the future for low-Earth orbit. Keywords: Autonomous navigation; Orbit determination; Orbit prediction; Estimation; Position Estimation; Theses.