Defines the default length of a mast, as shown in the 'Length' box of the 'Edit Structure' window. If the chosen mast is not available in the default length, the closest available length will be used.
Options:
A number that has a value of 0 or greater, expressed in metres.
Default Setting: 7.4 metres
Changing properties: If you wish to change the option of this property, your Project Settings Administrator must request a project settings change.