released an ILS script on the BI forums
which will somewhat simulate the ILS (Instrumental Landing System) in order to manually land at an airport with low visibility.
Quote TiGGa :
The easiest way to use the script with your missions is by adding an action menu entry to the airplane. As in the previous version made for ArmA1, you will get a somewhat primitive display of the glideslope's position. In this version, you will also see red bright rings which are following the glideslope. Those rings will currently spawn at a distance of 5 km to the airport, but you can change that in the script file itself. Once you fly below 5m, the script will terminate and all the rings will be deleted.
More information how to use this script in your mission can be found on the download page and in the included Readme.