# End station entry method

As you add each element to the alignment, fill out the fields required for the selected element type.

Line elements

To add a line to the alignment:

1. Select Line in the Element field.

2. Enter the Azimuth and End station to define the line.

   The End North and End East fields update automatically.

If this line is not the first line to be defined, the Azimuth field displays an azimuth calculated from the previous element.

To edit the azimuth, tap next to the Azimuth field and select Edit azimuth. A solid red circle is shown at the start of an element if adjoining elements are non tangential.

Arc elements

To add an arc to the alignment, select Arc in the Element field and then select the method to construct the arc:

If you select... | Then...
--- | ---
Radius and end station | Select the arc direction. Enter the Radius and End station to define the arc.
Deflection angle and end station | Select the arc direction. Enter the Angle and End station to define the arc.

The End North and End East fields automatically update.

The Azimuth field displays the azimuth as calculated from the previous element.

To edit the azimuth, tap next to the Azimuth field and select Edit azimuth. The icon preceding the element name is shown red if adjoining elements are non tangential or if adjoining elements defining a curve have different radii.

Entry transition/exit transition elements

To add a transition to the alignment:

1. Select Entry transition or Exit transition in the Element field.
2. Select the arc direction.

3. Enter the Start radius, End radius and Length to define the transition.

   The End North and End East fields update automatically.

For more information on supported transition types, see Transitions.

The Azimuth field displays the azimuth as calculated from the previous element. To edit the azimuth, tap next to the Azimuth field and select Edit azimuth. If the element is non tangential the icon at the start of the element is shown in red.

If the transition type is NSW cubic parabola the computed Transistion Xc value is displayed. If the transition is between two arcs the Transistion Xc displayed is the value computed for the common tangent point with the smaller of the two arcs.