Defining Minimum Safe Altitude (MSA) settings

The Minimum Safe Altitude (MSA) element is a graphical depiction of the altitude that allows adequate vertical clearance from nearby terrain and man-made obstacles, allowing proper navigational functions.

New MSA elements are created based on the Minimum Safe Altitude settings on the Element Settings pane on the Production Properties dialog box. These properties determine the default appearance and style of the newly-created MSA elements. Changing the settings does not alter existing MSA elements. Existing MSA elements can be updated by clicking the MSA Element tool, which will regenerate the MSA element based on updates to the data and/or the settings. The significant point on which the MSA element is based is defined in the MSAGroup feature class in the production database.

步骤:

1. Start ArcMap.
   提示:

   If the ArcMap - Getting Started dialog box appears, you can open a new or existing map document. You can also check the Do not show this dialog box in the future check box and click Open.

2. On the main menu, click Customize > Production > Production Properties.

   The Production Properties dialog box appears.

3. Click the Element Settings pane.
4. In the Minimum Safe Altitude section, click the cell next to Circle Diameter Units, click the drop-down arrow that appears, then choose the unit of measurement of the circle diameter.
5. Click the cell next to Circle Diameter and type the value you want.
6. Click the cell next to Circle Line Symbol, click the ellipsis button (...) that appears, then modify the circle line symbol properties.
7. Click the cell next to Identifier Font, click the ellipsis button (...) that appears, then modify the identifier font properties.
8. Click the cell next to Altitude Font, click the ellipsis button (...) that appears, then modify the altitude font properties.
9. If necessary, click the cell next to Reset Settings, click the drop-down arrow that appears, then choose True if you want to undo all the changes made to the MSA settings and restore the default settings.
10. Click OK to save the settings you have modified.

    These settings are applied to the new MSA elements you create in the future, unless the settings are modified again.