ILS in DCS: A-10C II Tank Killer Posted November 22 1 hour ago, jaylw314 said: Many airfields with an ILS have a non-precision Back Course approach based on the localizer. It's reverse-sensing, of course, but with an HSI that's a trivial issue. While this used to be the case some decades ago, back course approaches are rarely used these days (at least outside the US). Modern localizers use LPDA antennas with high front-to-back ratios ( > 20dB) which need modification in order to radiate a useful back course signal. Back course approaches are not approved for use in the EU (and Canada), and are extremely rare in the rest of the open ILS market (i.e. everywhere except the US and Russia, which have local monopolies).