The client has requested for a multiline for the air line. Upper linetype is continuous and Lower linetype is hidden. Anyone knows, how to write linetype definition for multiline and load at linetype manager. Refer to the following image.
 
zawhtetmaung2010-06-16 10:03:26

AutoCAD has currently only limited functionality for multi-line linetypes. You may consider using MLINE objects (multilines) or you would need to define a shape consisting of two lines and combine these shapes in a complex linetype.