Collision Assessment By Offset Ebl - Furuno FAR-2805 Series Operator's Manual

not the corresponding VRM is displayed.
The range marker changes its position
along the EBL with the rotation of the VRM
control.
Press the EBL OFF key to erase each
EBL.
000
350
No.2
340
330
EBL
320
310
300
290
280
270
Range scale
260
markers on EBLs
250
240
230
220
EBL
210
> 32.5°T<
200
190
180
298.0°T
Active EBL is indicated
with this marker.
1.18 Collision Assessment by
Offset EBL
The origin of the EBL can be placed any-
where with the trackball to enable mea-
surement of range and bearing between
any targets. This function is also useful
for assessment of the potential risk of
collision. To assess possibility of collision:
1. Press the EBL ON key to display or ac-
tivate an EBL (No.1 or 2).
2. Place the cursor (+) on a target of in-
terest (A in the illustrated example) by
operating the trackball.
3. Press the EBL OFFSET key on the
mode panel, and the origin of the ac-
tive EBL shifts to the cursor position.
Press the EBL OFFSET key again to
anchor the EBL origin.
4. After waiting for a few minutes (at least
3 minutes), operate the EBL control
until the EBL bisects the target at the
new position (A'). The EBL readout
shows the target ship's course, which
may be true or relative depending on
the settings on the RADAR 2 menu.
010
020
Target
030
blip
040
050
060
070
080
090
100
No.1
EBL
110
120
130
140
VRM
150
>0.978NM<
160
170
1.118NM
If relative motion is selected, it is also
possible to read CPA (Closest Point of
Approach) by using a VRM as shown
below (Figure (a)). If the EBL passes
through the sweep origin (own ship) as
illustrated (Figure (b)), the target ship
is on a collision course.
5. To return the EBL origin to the own
ship's position, press the EBL OFFSET
key again.
340
330
320
Cursor
310
300
290
A
280
1
A
270
260
No.1
250
EBL
240
230
220
210
EBL
200
> 140.0°R<
(a) Evaluating target ship's course and
CPA in relative motion mode
340
330
320
Cursor
310
300
290
A
280
1
A
270
260
250
240
230
220
210
EBL
200
> 118.2°R<
(b) Target ship on collision course
000
350 010
020
030
040
050
060
070
080
090
100
110
120
130
140
150
VRM
160
190
170 > 3.85NM<
180
000
350 010
020
030
040
050
060
070
080
090
100
110
120
130
140
150
VRM
160
190 170
180
> 0.00NM<
No.1
VRM
No.1
EBL
1-17