Icom MR-1220 Series Instruction Manual page 32

5
AIS RECEIVER
AIS operation
D About Lost targets
After a specified period of time (see the table below) has elapsed since the last AIS was received from a vessel, it
is considered a Lost Target.
The "Lost target" icon automatically disappears from the screen 6 minutes and 40 seconds after the vessel
becomes "Lost target."
Reference time to become a Lost target
• Class A/B
Vessel type
Vessel is at anchor or moored and
Class A
not moving faster than 3 knots
1
Vessel is not moving faster than 2
Class B
knots
Vessel is at anchor or moored and moving
2
faster than 3 knot
Vessel is moving between 0 and
Class A
14 knots
3
Vessel is moving between 2 and
Class B
14 knots
Vessel is moving between 0 and
Class A
14 knots while changing course
4
Vessel is moving between 2 and
Class B
14 knots while changing course
5 Vessel is moving between 14 and 23 knots
Vessel is moving between 14 and 23 knots
6
while changing course
7 Vessel is moving faster than 23 knots
Vessel is moving faster than 23 knots while
8
changing course
*1 AIS Class B does not provide information about the navigation status, anchored or moored.
*2 CS: Carrier-sense, *3 SO: Self organized
• Others
Nominal reporting
Category
SAR aircraft
Base station
AtoN
27
Nominal
reporting
interval Class A
3 min.
10 sec.
10 sec.
3 1 ⁄ 3
6 sec.
2 sec.
2 sec.
2 sec.
Lost target
interval maximum interval
10 sec. 60 sec.
10 sec. 60 sec.
3 min. 18 min.
Lost target
maximum
interval Class A
18 min.
— —
60 sec.
60 sec.
— —
60 sec.
sec.
— —
36 sec.
36 sec.
30 sec.
30 sec.
Nominal reporting Lost target maximum
interval Class B * interval Class B *
1
CS * 2 SO * 3 CS * 2
— — —
3 min. 3 min. 18 min.
N/A
— — —
30 sec. 30 sec. 180 sec.
— — —
30 sec. 30 sec. 180 sec.
30 sec. 15 sec. 180 sec.
30 sec. 15 sec. 180 sec.
30 sec. 5 sec. 180 sec.
30 sec. 5 sec. 180 sec.
1
SO * 3
—
18 min.
N/A
—
180 sec.
—
180 sec.
90 sec.
90 sec.
30 sec.
30 sec.