Local Cartesian Projection 

Release 9.2
Last modified August 3, 2007 
Print all topics in : "Supported map projections" 
This is a specialized map projection that does not take into account the curvature of the earth. It's designed for very largescale mapping applications.
The coordinates of the center of the area of interest define the origin of the local coordinate system. The plane is tangent to the spheroid at that point, and the differences in zvalues are negligible between corresponding points on the spheroid and the plane. Because the differences in zvalues are ignored, distortions will greatly increase beyond roughly 1° from the origin. This map projection is the same as the Orthographic projection, but supported on spheroids and spheres. The Orthographic projection is supported on spheres only.
Largescale mapping. Should not be used for areas greater than 1° from the origin if using ArcInfo workstation (coverages, GRIDs, or TINs). If using ArcMap, shapefiles, rasters other than GRIDs, or geodatabase data, can project almost a full hemisphere (89° from the origin).