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This paper presents the application of a relatively new concept, Required Navigation Performance (RNP), as a method to determine requirements for aircraft surface movement guidance and control. Currently, navigation standards do not exist for low visibility aircraft operations on runway and taxiway surfaces. Whereas there are enabling technologies under evaluation for aircraft guidance and Air Traffic Control surveillance on the airport surface, there are no performance requirements available to judge the suitability of specific systems. A top-down process is applied, starting with a target level of safety for each surface operation. RNP requirements are allocated to ground and airborne equipment and an approach is presented to validate the RNP allocations using a Functional Hazard Assessment (FHA).

In this article, we study technical issues involving wide-area surveillance system using multilateration sensors. A satellite clock reference scheme is seen as a better solution for synchronization of widely dispersed sensors. We then described a direct solution approach to derive target positions. Techniques are developed for resolving solution ambiguities, including different sensor combinations and tracking algorithms. It is also proposed that signal strength comparison and other techniques be used to enhance tracking performance and accuracies with Mode A/C data. Finally, some recent flight test results are shown to demonstrate the feasibility of multilateration system for wide-area surveillance.

Legislative design was a critical question at the 1787 Constitutional Convention. The peculiar compromise that was struck-featuring proportional and republican elements-defies the logic of the Convention's majority rule. We investigate how in establishing the new national legislature, small state delegates were able to prevail over the large state majority and secure the Connecticut Compromise. We argue that the small state coalition's victory owes to their strategy at a critical juncture: the Gerry Committee. The Gerry Committee amplified the contours of the debate over legislative design and the careful curation of its participants precipitated a shift of structural and creative freedom allowing for the consideration of alternative solutions. The Committee produced an environment favorable to a compromise on legislative structure and power by manipulating the policy dimensions connecting representation, taxation, and slavery. Participant curation was essential in allowing political opponents-the small states-to overcome unfavorable conditions, maximize utility, and craft a proposal capable of approval by delegates and eventual constitutional ratification.

Parts of this research were performed under contract to the U.S. DOT Volpe Center, FAA, and NASA. This paper contains only the )understanding and views of the authors and is not intended to represent the official position of the U.S. Govemment or ICAO.