A new article reproducing an October 1949 proposal for the Supersonic Naval Ordnance Research Track (Project SNORT) is up at a RetroMechanix.com (http://retromechanix.com/articles/aerospace/supersonic-naval-ordnance-research-track-project-snort-proposal-of-1949/):
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The accompanying gallery features 30 images, including numerous artist's impressions and schematics of proposed rocket-powered sleds and test vehicles. Project SNORT went on to actually be built and has contributed a great deal of valuable data to the development of a wide range of rockets and missiles. This document provides an interesting overview of how the track was originally designed and conceived.