BRAVO!!!!! I must admit, you are better than me. I'm only a novice at this. I thought sine and cosine could only be used with right angle triangles :damn: Would you give me copyright to explain this method as I did with the stationary one?

No copyright necessary, geezer. There's no pride in authorship here in the forum, you're free to use this at will.

All that is required is to research solving Oblique Plane Triangles. Just Google it and you're in business.

One other thing, I'm not better than you...we're all equals here...but, I'm a lot older than you are :D

I'm not sure if you want me to explain how it works..(?)

...just in case you do...here goes:

1) We're at periscope depth (PD) and on course 269° (True) @ 3kn., when we spot the tgt. BR 068° (Relative) at Range 3800m. Start the stopwatch.

2) Rule of Three (using yards=3 min., using metric 3min 15sec) We're using metric so 3:15 it is. When time elapses, we take 2nd bearing on tgt., which is now BR 064° @ 3200m. (note 4° difference).

3) We now have a large narrow oblique triangle ABC with apex angle A = 4°; angle B = 64° since it is a vertical angle created by the sub's track as part of triangle BEF; angle C = 112° the supplementary to straight line ACD (180-68=112).

4) We solve triangle ABC using the law of sines giving us the lengths of AB and AC.

5) AB + BE = 7665m; AC + CD = 7187m.

6) Line DF = the tgt's. track. Line segment DE = distance tgt travelled in 3:15, which is solved using the Law of Cosines. In my example it = 684m, according to the rule of three = 6.84 kn. ~ 7 kn.

Course:

269° T (Own course)
+064° R (Tgt Bearing)
333°
-180° (reciprical)
153°
+054 (Add Port AOB, Subtract Starboard AOB)
207° T (Target's course)


All the best,

How can you know your older than me? Or are you talking about forum-wise age?

Fun with math......I thought that was just a myth!

Oh yes mathematics is the one and only true form of art in this word. And they can be fun. Trust me I spent my life learning them and using them in every and not so everyday problems;)

...geezer if you were born in '38, then you're older :rock:

lets do the math..............:rotfl:

Ohhhhhh, you are a "SEASONED" skipper.

Allow me to ask you. What exactly is it you do for a living, or for a hobby (i wouldnt blame you for being retired).

Check his last post 'Seasoned Skipper' :D

Click on my name on the left side and check out my profile...:arrgh!:

I'm whats referred to as an OUA (old ugly arse) aka curmudgeon aka old fart...:smug:

heck, I'll answer to anything, as long as it's for payday or chow!!

cheers,

That's right call me what you want but not late for dinner:up:

o.t.

I'm Homer Simpson of the Borg. Prepare to be assim... doh...cookies!

This is amazing
 

I just came across this and thought I'd try to understand it. If it's ok, I'll be emailing for help (if I get stuck)?

Thanks

Not to put a damper on your enthusiasm or anything, but you do realize this thread is six years old, right?
:hmmm:

Hello All.

Still lurking the forum(s). Would it help if I posted a graphic of the solution? A pic is worth 1k words.

Cheers.