its a format for working out a solution
R=range
B=bearing rate
R=RSA(relative speed across)
O=OSA(own speed across)
T=TSA (targets speed across)
S= speed
A=ATB
R=reciprocal bearing
C=course
and DOT which distance off track which is always handy
range = 2x RSA /BEARING RATE
BEARING RATE = 2X RSA/ RANGE
RSA= BEARING RATEXRANGE/2
OSA =SIN REL BRG X OWN SPEED
TSA = SIN ATB X TGT SPEED
SPEED =TSA/SIN ATB
ATB =TSA/SPEED INV SIN
DOT = RANGE X SIN ATB
THIS IS HOW WE GET TO A BEARING RATE ONLY SOLUTION IN THE RN SOMETIMES YOU NEED TO GUESTIMATE SPEED AND RANGE HERES AND EXAMPLE
own course 030 speed 8 tgt range 16k bearing rate 1.0L bearing 060 speed 16 find tgt course ( if you go down the tote same directions add different subtract opposite if you go up the tote differnt add same subtract)
RANGE 16000YDS
BEARING RATE 1.0L
RSA 8L
OSA 4L
TSA 12L
SP 16
ATB 48PT
RECIP BRG 240
COURSE 288 (pt atb plus stb subtract)
DOT 12k
you can do this on a calculator using the formulae or on the old bearing rate widger standard issue on RN subs or if you good enough in your head
for intance sin atb 30 =.5 or half so if the range is 10k then the dot =5k( dot is a estimate of how close the target is going to come it dosent take into account own speed so it may come closer but its a quick way of making sure your safe)
