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ENCLOSURE A HIGHWAY DESIGN MANUAL 400-27 November 1,2001 E Figure 407E is the template for the Topic 407 - Truck and Bus AASHTO Bus Design Vehicle turning on a Turning Templates 12.8-meter radius. Figures 407A through E are taming templates at an approximate scale of 1:500 for the three types of design vehicles described in Topic 404. A computer model of truck offtracking generated these"hard copy"templates. The printed templates can be used as overlays to evaluate the adequacy of the geometric layout of a curve when reproduced on clear film and scaled to match the highway drawings. The lines on the template delineate the path of the wheels and the body of the vehicle as the truck moves through the tarn. These lines must clear any `obstacles" including curbs, islands, adjacent lanes, sign structures, traffic delineators, traffic signal and lighting poles, guardrails, trees and rock outcrops. If any 'obstacles" are encroached by the vehicle path on the template, then an alternative design is needed. If the wheel paths stay within the roadbed without "hitting" any obstacles, then the geometry is adequate for that design vehicle. See Topic 404 for information on the design vehicles. A 15-meter and 18-meter radius template is given for each of the STAA and California Legal Design vehicles. The radius of the template is measured to the outside front wheel path through the curve. The 18-meter radius template is more conservative and is preferred. The 18-meter radius template requires less right of way on the inside of the curve, and it leaves a margin of error for the truck driver. The 18-meter radius template should be used for conditions where the vehicle may not be required to stop before entering the intersection. The 15-meter radius template can be used if the 18- meter radius template does not clear all obstacles. A 15-meter radius is the minimum radius that a STAA or California Design Vehicle can navigate. • Figures 407A and B are templates for the STAA Design Vehicle turning on 15- meter and 18-meter radii,respectively. Figures 407C and D are templates for the California Design Vehicle taming on 15- meter and 18-meter radii,respectively.