STBY/ON

RADAR PLOTTING TECHNIQUES

Capt. Arnel Malaga

STBY/ON

Radar plotting tips, radar plotting made easyRadar Plotting FormulasTime to C.P.A. = m" to C.P.A. x Plotting Interval Distance r" to m" e" to r" = Own ships speed x Plotting interval 60 Target Course = e" through Centre of m" Target speed = Distance from e" to m" x 60 Minutes from r" to m"

Capt. Arnel Malaga

STBY/ON

Tidal problems using RadarDrift = Distance from m" to e"

Set = Direction from m" to e"

Rate of Tide = Distance from m" to e" x 60 Minutes from r" to m"

Capt. Arnel Malaga

STBY/ON

BASIC RADAR PLOT

Warning ! ! ! Watch to see if you are using Relative or True Compass Bearings. Bearings. Using a relative bearing is how you would take a compass bearing of another vessel. vessel.

Capt. Arnel Malaga

STBY/OFF

EXIT

Capt. Arnel Malaga

STBY/ON

Capt. Arnel Malaga

Single Targetr is the targets first plot rOwn Ship Course & Speed

e

The direction and length of the points e r is your own ship course and speed

Capt. Arnel Malaga

m is the targets second plot rOwn Ship Course & Speed

m

e

r m is the targets relative motion where: - relative course is the direction - relative speed is the length of r m / the time interval

Capt. Arnel Malaga

r mTarget Course Target Speed=Dist/Time Interval

e

e m is the targets true motion where: - target course is the direction - target speed is the length of e m / the time interval

Capt. Arnel Malaga

AVOIDANCE COURSE

Capt. Arnel Malaga

BNCPA

Avoidance Course

mx is the point of execution of avoidance r rx NCPA m mx e

NDRM e rx is the avoidance course

rx m is the targets new relative motion line where: - the direction is the targets new direction of relative motion - target new relative speed is the length of rx m / the time intervalCapt. Arnel Malaga

AVOIDANCE SPEED

Capt. Arnel Malaga

BNCPA

mx is the point of execution of avoidance r m mx rx e

NCPA

NDRM e rx is the avoidance speed rx m is the targets new relative motion line where: - the direction is the targets new direction of relative motion - target new relative speed is the length of rx m / the time intervalCapt. Arnel Malaga

MULTIPLE TARGETS

Capt. Arnel Malaga

STBY/ON

r m mx e

rx

Capt. Arnel Malaga