Collision Assessment By Offset Ebl; How To Assess Risk Of Collision Using The Offset Ebl - Furuno FAR-2218-BB Operator's Manual

1. OPERATIONAL OVERVIEW
1.34

Collision Assessment by Offset EBL

The origin of the EBL can be placed anywhere to enable measurement of range and
bearing between any two targets. This function is also useful for assessment of the
potential risk of collision. It is possible to read CPA (Closest Point of Approach) by us-
ing the EBL range marker as shown in (a) in the illustration below. If the EBL passes
through the sweep origin (own ship) as shown in (b) in the illustration below, the target
ship is on a collision course.
340
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A
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1
A
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No. 1
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210
EBL
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1.34.1

How to assess risk of collision using the offset EBL

There are two methods for assessing risk collision. You can use the control unit or the
[CURSOR] menu.
Using the control unit (RCU-014)
1. Press the EBL ON key to display or activate an EBL (EBL1 or EBL2).
2. Place the cursor on a target appearing as threatening (indicated as "A" in the ex-
ample figure on the previous page).
3. Press the EBL OFFSET key and the origin of the active EBL shifts to the cursor
position.
4. Press the EBL OFFSET key again to anchor the EBL origin.
5. After waiting for a few minutes (at least 3 minutes), operate the EBL knob until the
EBL bisects the target at the new position (A
ship's course, which can be true or relative depending on the EBL bearing refer-
ence setting.
Note: If relative motion is selected, it is also possible to read CPA by using the
range marker as shown in left-hand figure at the top of the next page. If the EBL
passes through the sweep origin (own ship) as illustrated in the right-hand figure
above, the target ship is on a collision course.
6. To return the EBL origin to the own ship's position, then press the EBL OFFSET
key.
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EBL
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range
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marker
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(a)
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A
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No. 1
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EBL
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1
). The EBL readout shows the target
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range
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marker
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150 (b)
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