You can create elliptical arc by several construction types. Click View, Geom Curve to toggle the display of individual curve.
To create a elliptical arc:
Click Elliptical Arc (Curve toolbar) or click Geometry, Curve, Elliptical Arc .
In the dialog , select the type of you want to create the circular arc:
Parameters. Create an elliptical arc by center, normal, major, minor radius, start and end angle parameters.You can also sketch elliptical arcs when "Sketch on Plane" is checked.
Point/Axis. Create an elliptical arc by select a center point, an axis and define the major and minor radius, start and end angle.
Coordinate. Create an elliptical arc by select a coordinate system, and define the major and minor radius, start and end angle.