Bearing and Distance Measurement (ERBL)

The ERBL (Electronic Bearing and Range Line) tool is designed to measure directions (bearings) and distances from the vessel to an arbitrary point, or between two arbitrary points on the chart.

Tool activation

The tool is activated by clicking the ERBL icon in the tool selection menu. When activated, the ECDIS cursor changes to .

Important

In bearing and distance measurement mode, chart panning is blocked!

Measuring bearing and distance from the vessel

To measure the bearing and distance from the current vessel position, left-click (tap) the point of interest on the chart.

Features:

• The bearing is measured from the current vessel position to the selected point

• The distance is calculated automatically

• If the mouse button is released (finger lifted), the initial point resets to the vessel position

Measuring between two points

To measure between two arbitrary points on the chart:

1. Press and hold the left mouse button at the first point

2. Drag the cursor to the second point

3. Release the mouse button

Measurement parameters

Parameter	Description
Bearing	The angle between the north direction and the measurement line (in degrees). Forward direction (T) — from the vessel to the point, and reverse direction (R) — from the point to the vessel. When measuring between two arbitrary points, only the forward direction from the first point to the second is displayed
Distance	The distance between the measurement points (in nautical miles, meters, or kilometers)
Origin point	The vessel position or the first selected point on the chart
Endpoint	The selected measurement point

Note

The ERBL line type is always a great circle (GC).

Operating features

Measurement modes:

• From vessel: click a point on the chart — measurement from the current vessel position

• Between points: press and drag — measurement between two arbitrary points

Indication:

• The measurement line is displayed on the chart

• Measurement parameters (bearing and distance) are shown in the information window or on the chart

Reset:

• Releasing the mouse button without dragging returns to the origin point (vessel position)

• To start a new measurement, simply select a new point

Tip

Use the ERBL tool for rapid estimation of distances and directions when planning maneuvers or working with navigational objects on the chart.

For accurate measurements, select points on the chart considering the current scale — the larger the scale, the more accurate the measurement.

Note

The ERBL tool is an indispensable means for performing navigational calculations and assessing the situation on the chart without the need to construct complex graphical plots.