I've got field collected data in NAD27 zone 11S (matched the paper topo maps being used in field) and need to bring into ArcMap. When selecting the import coordinate system, I cannot find zone 11S (only 11N).
Any help would be greatly appreciated.
Since you are using a north american datum, I presume that you are in north america. The UTM 11S is kind of a misnomer and generally only used with paper maps designating the 6x8 degree coordinate block. In the world of gps and mapping technology, the world is now view largely as N for north or S for south, refering to the equator. I can almost assure you that utm 11N will be appropriate