The Crane Pad tab (figure 115) - This option, when checked, is intended to be used in mountainous areas in order to prevent the optimisers placing turbines of this type in knife-edge ridges. It allows the user to specify a series of tests to be carried out on the terrain surrounding a prospective turbine location. The diagram at in the lower half of the dialogue is for display purposes only and represents the turbine rotor for scale against the locations of the terrain checks to be carried out. In the case below, the tests look for a relatively flat area on one side of the turbine comprising five consecutive points out of a total of 16 which are <5% grade from the turbine location. An alternative configuration might be to place the turbine at the centre of circle half that size and require that most or all of the surrounding points fall within the specified tolerance.