
<section id='BaseOps_RadialAndArcChunks_id'
webfilename='radialandarcchunks'>
    <title>
        Editing Radials and DME Arcs
    </title>
    <para>
        A <termtext>radial</termtext> is a line on a map that begins at
        a <link target='#BaseOps_PointObjectChunks_id'>navigational aid</link>
        and continues indefinitely along a specified heading.
    </para>
    <exhibit>
        <img src='BaseOps_Radial_Figure.png' standard_colors='true'/>
    </exhibit>
    <para>
        A <termtext>DME arc</termtext> is a full or partial circle on
        a map that is centered on a navigational aid.
    </para>
    <exhibit>
        <img src='BaseOps_Arc_Figure.png' standard_colors='true'/>
    </exhibit>
    <para>
        Radials and arcs are often used to define portions of <link
        target='#BaseOps_FlightTrackChunk_id'>flight tracks</link> (for
        example, begin a turn when the track intersects a particular radial)
        and <link target='#BaseOps_FlightProfileChunk_id'>flight profiles</link>
        (for example, begin a descent when a particular DME arc is reached).
    </para>
    <para>
        BaseOps allows you to add radials and DME arcs to the maps of
        flight tracks and flight profiles. This involves three steps.
    </para>
    <orderedlist>
        <listitem>
            <para>
                If it does not already exist, add the navigational aid that anchors
                the radial or arc. See <iref
                target='BaseOps_PointObjectChunks_id'/>.
            </para>
        </listitem>
        <listitem>
            <para>
                If it does not already exist, create the radial or arc as described
                in this chapter.
            </para>
        </listitem>
        <listitem>
            <para>
                Add the radial or arc to the map of the flight track or flight
                profile, as described in <iref
                target='BaseOps_AnnotatingMapsWithObjects_id'/>.
            </para>
        </listitem>
    </orderedlist>
    <para>
        To work with radials or DME arcs, choose Radials or Arcs, respectively,
        from the <link target='#BaseOps_ListPane_id'>object type selector
        dropdown list</link>. Radials and arcs can be added, duplicated,
        and deleted as described in <iref
        target='BaseOps_ListPane_id'/>.
    </para>
    <para>
        To edit a radial or arc, first select it in the <link
        target='#BaseOps_ListPane_id'>object list</link>, then edit its
        properties in the <link
        target='#WCF_ApplicationMainWindow_id'>text pane</link>.
    </para>
    <exhibit>
        <img src='BaseOps_RadialAndArcChunks_ScreenCap.png'
        standard_colors='true'/>
    </exhibit>
    <para>
        Both radials and arcs have the following properties.
    </para>
    <unorderedlist>
        [-include "BaseOps_Name_ListItem.rxl"     ObjectTypeName='radial or arc'-]
        [-include "BaseOps_Notes_ListItem.rxl"    ObjectTypeName='radial or arc'-]
        <listitem>
            <para>
                <italic>NavAid</italic> - The navigational aid that anchors the
                radial or arc. Select the navigational aid from the dropdown list.
                Press the Add Navigational Aid button <img
                src='intres:WCF_AddPlusSignToolbarButtonBitmap'/> to add a new
                navigational aid. Press the Go To Navigational Aid button <img
                src='intres:BaseOps_GotoToolbarButtonBitmap'/> to edit the selected
                navigational aid.
            </para>
        </listitem>
    </unorderedlist>
    <para>
        Radials have the following additional properties.
    </para>
    <unorderedlist>
        <listitem>
            <para>
                <italic>Heading</italic> - The direction of the radial as seen
                from the navigational aid, expressed in degrees east of magnetic
                north.
            </para>
        </listitem>
    </unorderedlist>
    <para>
        DME arcs have the following additional properties.
    </para>
    <unorderedlist>
        <listitem>
            <para>
                <italic>Arc Start Heading</italic> - The direction of the beginning
                of the arc, as seen from the navigational aid, expressed in degrees
                east of magnetic north.
            </para>
        </listitem>
        <listitem>
            <para>
                <italic>Arc Span Angle</italic> - The length of the arc, in degrees
                clockwise from the beginning. For DME circles, specify a span
                angle of 360°.
            </para>
        </listitem>
        <listitem>
            <para>
                <italic>Radius</italic> - The radius of the arc.
            </para>
            <para>
                You can change the units used to specify the radius: see <iref
                target='BaseOps_CaseUnits_id'/>.
            </para>
        </listitem>
    </unorderedlist>
</section>
