tote for working out manual solutions

[micky1up]

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)

[PeriscopeDepth]

Thank you micky, this kind of stuff is great (especially when you have a programmable calculator handy). Anything else like this that you're allowed to share would be most welcome.

PD

[micky1up]

sins in your head using clock face rule


imagine a clock

10mins past = 1/6th
15mins past -=1/4
20 past= 1/3
30 mins past easy = 1/2
40 =2/3
anything over 45 add 25 and call it a percentage

so distance of track atb 50 at 10000= 50 +25(over 45 add 25)call at percentage 75% dot =7500yds

[Bill Nichols]

Originally Posted by micky1up

sins in your head using clock face rule


imagine a clock

10mins past = 1/6th
15mins past -=1/4
20 past= 1/3
30 mins past easy = 1/2
40 =2/3
anything over 45 add 25 and call it a percentage

so distance of track atb 50 at 10000= 50 +25(over 45 add 25)call at percentage 75% dot =7500yds

Another (equivalent) way to estimate sines is:

sin(X degrees) = X / 60

which works surprisingly well for X < about 45 degrees.

[Pisces]

Originally Posted by Bill Nichols

Another (equivalent) way to estimate sines is:

sin(X degrees) = X / 60

which works surprisingly well for X < about 45 degrees.

My left brain says: " Ugh!! Yuck! Up to 6% error. How horrible unprecise."

My right brain says: "Wow! What a beautiful picture. This helps to get things in perspective"

I wonder which one is going to win this fight. Great help guys.

[Bill Nichols]

Originally Posted by Pisces

My left brain says: " Ugh!! Yuck! Up to 6% error. How horrible unprecise."

My right brain says: "Wow! What a beautiful picture. This helps to get things in perspective"

I wonder which one is going to win this fight. Great help guys.

Your left brain had better get out of the way... what I posted was taught to me in the US Navy's submarine school.

[Linton]

Would anybody be able to format the above into a useful reference sheet to use in the game?

[OneShot]

A bit more elaboration on it would be nice ... for example what some of the units mean, ie "L" and "PT" for starters. Perfect would be representation with real math symbols and a nice legend for the unit (write - scan - post ... sorta).

Cheers
OS