I'm reviewing charts in anticipation of a checkride, I can't find anywhere on the chart [ http://download.aopa.org/ustprocs/current/NC-1/bis_ils_or_loc_rwy_31.pdf ]
the meaning of the ** before the S-ILS 31 DA. Would the explanation be somewhere else in the book of approach charts? My book is in the airplane so all I have here is digital charts. Thanks!