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-   -   Fast calculating speed,small tutorial with pix (https://www.subsim.com/radioroom/showthread.php?t=103166)

Dimitrius07 01-04-07 06:05 PM

Fast calculating speed,small tutorial with pix
 
Hi everybody ;)

I want to represent to you my way how i got speed of the target - with out waste to much time - time in thise game is almost always against you :D

Ok here we go - :arrgh!:

First we need to indification the target we want to destroy :rock:
http://img113.imageshack.us/img113/9...2007057ms6.jpg


As you notice in the picture we have are first info - little Tram Steamer

Now lets get a second info - time.
http://img490.imageshack.us/img490/9...0070571vq9.jpg

note - don`t move your uzo or perescop - in thise time

http://img296.imageshack.us/img296/9...2007058tr8.jpg

As you can see - we have now another info - time in sec (32 sec)

Now - lets do some Matematic :|\\

78.5 to divide 32 = aprox 2.453125
2.554545 its a meters per second - lets convert thise in knots
2.554545 To increase 1.946 = 4.7737 knots

Thise is our speed - since in the example the target is not in 90 degree - we can make it aprox 5 knots.
Note
Thise tutorial made when my uboat was on surface with speed 0 knots.

If you unable to unable to do the calculation in all stop - there is my personal tip
help me many times.

Lets say we move forward to the target submerge in constant speed of 2 knots.
Do the calculation exacly as i shown in the pictures. But when you get a final result simply you need To add 70% or 75% to the final result
for examp
you mofing forward to the target in 2 knots
you made a calculation and you get let say 5.45 knots
5.45 To add 1.5 = 6.95 or 7 knots the speed of the target

If you moving back from your target you need To take away 70% or 75%

for examp
you moving in back standart in 2 knots
your result is 9.76 knots
9.76 - 1.5 = 8.26 knots the speed of the target
----------------------------------------------------------------------------

I hope i actually help some one - with thise tutorial.

Good luck :yep: :up:



CaptainNemo12 01-04-07 07:41 PM

Quote:

Originally Posted by Dimitrius07
Hi everybody ;)


Thise is our speed - since in the example the target is not in 90 degree - we can make it aprox 5 knots.

What do you mean not at 90 degrees? The ship looks like it's at perfectly 90 degrees from your point of view.... Or do you mean not at 90 degrees from the the 0 bearing on your UZO?

Anyways, great tutorial!!!

P.S.: Where did you get the 1.5 in your answer?

CaptainNemo12 01-04-07 07:42 PM

Quote:

Originally Posted by Dimitrius07

Thise is our speed - since in the example the target is not in 90 degree - we can make it aprox 5 knots.

What do you mean not at 90 degrees? The ship looks like it's at perfectly 90 degrees from your point of view.... Or do you mean not at 90 degrees from the the 0 bearing on your UZO?

Anyways, great tutorial!!!:D

P.S.: Where did you get the 1.5 in your answer?

RAM 01-04-07 08:06 PM

Quote:

Originally Posted by CaptainNemo12

What do you mean not at 90 degrees? The ship looks like it's at perfectly 90 degrees from your point of view....


nope, the ship is not at 90º AOB. Just look at the ID book, the shape of the bridge. Then look at the ship's bridge in the pic. The ship has a noticeable deviation from 90 deg. It's hard to say from the pic, but I'd say that the AoB is less than 90 deg (the ship is coming nearer the Uboat as it advances). I'd give it a 75º AoB. Maybe Dmitrius can tell me how wrong I am in my estimation (I'm still trying to learn manual shooting)



Dmitrius, I feel like slamming my head against a wall for not thinking about this one before :damn: . It's so simple that it's beautiful!!!!. As I said before I'm trying to master the art of manual firing, and estimating speed in fast-shot setups has always been very complicated for me...however I don't understand those calculations very well. Let me see.

I measure the time the ship takes to travel it's own lenght on scope or Uzo. So far so good.
I get, say, 25 seconds for that same 78.5m ship.
78.5/25=3.14 meters/second.
I can do easily a translation of 3.14 m/s to KM/H (would be 3.14x3600/1000, result is around 11,3km/H), then translate the result to knots...(dividing by 1.8 would be enough for a rough number, result is around 6.1knots)

but...how do you change 3.14M/s directly to knots?...I'm a bit at loss here...




One further question, just in case you have the answer...for Uboat surface speeds what would be the correction factor?. Say, what about 4 knots?. And 6?.

I ask because I do a lot of attacks at 4 or higher knots if at periscope depth, just to be sure I am keeping the right depth during the attack...

johan_d 01-04-07 08:54 PM

when its this close I just press fire..

Dimitrius07 01-04-07 09:00 PM

RAM sorry but i don`t have a right answer to your question because i never do target solution in such high speed. And i also don`t recomed to you. The main reason is not only accurasity is also a mining to stay silent.
Moreover 2 knots will maintane the depth

Dimitrius07 01-04-07 09:04 PM

Quote:

Originally Posted by CaptainNemo12
Quote:

Originally Posted by Dimitrius07

Thise is our speed - since in the example the target is not in 90 degree - we can make it aprox 5 knots.

What do you mean not at 90 degrees? The ship looks like it's at perfectly 90 degrees from your point of view.... Or do you mean not at 90 degrees from the the 0 bearing on your UZO?

Anyways, great tutorial!!!:D

P.S.: Where did you get the 1.5 in your answer?

You will be surprised
Its not even 80 :D

To your second question
Its my personal discovering - and i wanted to share thise with others :p ;)

wamphyri 01-04-07 09:11 PM

The one question that RAM had that I'd like to see answered is how you convert the meters/second to knots. That's the only part i'm also not 100% on.

Dimitrius07 01-04-07 09:15 PM

I found the convert info on some Russian web saite, and as you can see its also correct ;)

_Seth_ 01-04-07 09:17 PM

Quote:

Originally Posted by wamphyri
The one question that RAM had that I'd like to see answered is how you convert the meters/second to knots. That's the only part i'm also not 100% on.

M/S x 1,946 = Knots

Trust me, Dimitrius07 has this exactly right(tested,tested and tested..).

IE: 14 meter pr second X (multiplied with) 1,946 = 27, 2 (knots).
Easy remembering: 1,946 = 1946 was the year after the end of WWII

MONOLITH 01-04-07 10:53 PM

Good stuff.

The only part I didn't get, was the 70% add or minus for ownship speed.

He did 1.5 added to 5.45.

1.5 = 27.5% (of 5.45).

So he's actually adding 25 to 30% (which counters 70 to 75%) so is it just the way he phrased the sentence that's wrong?

azn_132 01-04-07 11:17 PM

Quote:

Originally Posted by CaptainNemo12
Quote:

Originally Posted by Dimitrius07

Thise is our speed - since in the example the target is not in 90 degree - we can make it aprox 5 knots.

What do you mean not at 90 degrees? The ship looks like it's at perfectly 90 degrees from your point of view.... Or do you mean not at 90 degrees from the the 0 bearing on your UZO?

Anyways, great tutorial!!!:D

P.S.: Where did you get the 1.5 in your answer?

U double posted.

_Seth_ 01-04-07 11:39 PM

:rotfl:Noone is gonna eat him for that...

_Seth_ 01-04-07 11:45 PM

Quote:

Originally Posted by MONOLITH
Good stuff.

The only part I didn't get, was the 70% add or minus for ownship speed.

He did 1.5 added to 5.45.

1.5 = 27.5% (of 5.45).

So he's actually adding 25 to 30% (which counters 70 to 75%) so is it just the way he phrased the sentence that's wrong?

Yes, it has to be. I get the same result as you. 5,45 X 27,5 divided with 100 = 1,498 ~ 1,5.

Kumando 01-05-07 05:58 AM

Quote:

Originally Posted by _Seth_
Quote:

Originally Posted by wamphyri
The one question that RAM had that I'd like to see answered is how you convert the meters/second to knots. That's the only part i'm also not 100% on.

M/S x 1,946 = Knots

Trust me, Dimitrius07 has this exactly right(tested,tested and tested..).

IE: 14 meter pr second X (multiplied with) 1,946 = 27, 2 (knots).
Easy remembering: 1,946 = 1946 was the year after the end of WWII

Round to 1.95 its more easy ;) .


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