The Local Tangent Plane as Primary Methodological Reference: Evidence that Curvature Constitutes a Secondary Computational Insertion in Aircraft Dynamic and Tracking Models

Abstract

Technical literature in aerospace dynamics and target tracking consistently initiates models from a flat or local-tangent-plane reference frame. This paper examines that practice through primary sources-Crouse (2015), Stewart et al. (2010), and multiple NASA technical reports-and argues that the local tangent plane functions as a topographical, stationary planar surface in operational modelling. Ellipsoidal curvature terms appear only as subsequent adaptations. The analysis treats the local planar frame as the default computational baseline and the insertion of curvature as a post-processing construct rather than a primary empirical observation.