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I'm goin' down
02-11-09, 12:47 PM
What the hell do you do when the TDC rounds speed to the nearest knot? E.g. Tarpet speed = 7.5 kts. TDC records = either 8.0 kts. or 7.0 kts. 1. How do you compensate for the 1/2 kt. speed differential in manual targeting? Dick O'Kane method? Cromwell attack technique?

breadcatcher101
02-11-09, 01:32 PM
I have had luck in going with 8 knots for my first shot then switch to 7 for the second unless it is a small ship, then I would go with 7 knots and hit aft of the engine room.

RickC Sniper
02-11-09, 02:18 PM
I'm usually close enough to target that being off by .5 of a knot won't matter.

Using the O'Kane method, you could fire about 1\3 of shiplength early if it rounded up, and 1\3 shiplength late if it rounded down.

Soundman
02-11-09, 02:42 PM
Well I can tell you that I have experimented with "fractions of knots" and while the Postion Keeper will only show whole numbers, you can enter 6.5 knots and it will be computed AND factored into the solution. I sometimes fire from 3000 yards using the "O'Kane Method" and from that distance, 1/2 knot or even 1/4 knot can make the difference between a hit or miss or whether you hit dead center. If you want precision targeting, it is to your advantage to nail the speed down as accurately as possible and enter the speed accordingly. To those that may say "round it to the nearest knot, it won't matter", I disagree.

Try this experiment.....set up a straight out the tube shot at zero degrees, zero knots, 90 degrees starboard AOB and fire. Then enter 1/2 knot speed and fire. You will see the fish run to the right of the first one.

AVGWarhawk
02-11-09, 03:26 PM
I'm usually close enough to target that being off by .5 of a knot won't matter.

Using the O'Kane method, you could fire about 1\3 of shiplength early if it rounded up, and 1\3 shiplength late if it rounded down.

:up: .5 knots will some difference but not by much IMO. One can always make a spread of 1 degree to compensate. Yes? No?

Soundman
02-11-09, 04:27 PM
I guess I'm a perfectionist. I want to hit as near to where I aim as possible.

I just tried my own experiment like I suggested above. I was stationary looking at a Medium Modern Composite Freighter(also stationary) from 1500 yards. I set up a zero degree, zero knot, 90 degree AOB and zero gyro angle, just like you would an O'Kane shot. I aimed center ship and fired. Then I added and entered 1/2 knot speed and fired number 2. The first hit exactly dead center of ship. The second hit just near the forward mast. This is about a quarter of the ships length. I don't know off hand how long this boat is, but to me a 1/4 ships length is quite a variance and if you are firing from a longer distance, we could be talking a miss here.

I use the the O'Kane method often, as it does allow for precision targeting and if you take the time to measure speed very accurately and enter that value, you should hit the point at which the boat crosses the lubber line when you fire. I measure speed for at least 12 minutes or longer (3 minutes won't allow much speed detail) and use a calculator to get the fractions of knots. I see two major advantages here.. (1) You can fire, even from long distances of over 3000 yards and hit the target where you intend. I have found that when firing on an escorted boat, shooting from about 3800 yards allows you the ability to shoot and scoot and the escorts never come close to finding you. (2) Hitting where you aim saves you ordinance because you can hit the juicy parts of the ship, which allows fewer fish to put'm under. As I have said, if you want precision....:know:

This experiment is easy to verify. I used the Sub School artillary mission. Just make sure you dive fast after entering the mission because they WILL be shooting at you.

AVGWarhawk
02-11-09, 04:41 PM
Well, here is my take on the 3000 yards shots. They happened and with some success. Doctrine was 1500 yards are less to take the shot. I would venture to guess any error in calculation at 3000 yards will be much more pronounced then at 1500 yards. So yes, .5 of a knot at 3000 yards could be a football field miss. Also, doctrine called for 3 torps because there was other factors involved that spoil the skipper whole day. Water state, currents, etc. I find that the ingame speed is always a whole number actual and not a number and .5. Question is, if your calculations are always coming up .5, which way do you go? Round down or round up? I usually round down. I get to my 1500 yard or less (BTW, I use the O'Kane method all the time now) and send out my first torp just as the bow crosses the line on the scope then the others at the larger structures of the vessel. Very rarely do I miss forward or aft of the vessel. I do not use the lock anymore. Waste of time IMO. Get in there, be aggressive and fire when you can see the rivets on the ships:rock: Get the speed right on the target and the rest falls into place.

Oh, some one mentioned changing the torpedo speed as you fire them. If I'm really unsure of the speed, I will dial in the first to what I believe the speed to be, the second one knot slower and the third one not faster. One of them, if not a dud, will find the mark.

Soundman
02-11-09, 05:00 PM
I find that the ingame speed is always a whole number actual and not a number and .5. Question is, if your calculations are always coming up .5, which way do you go? Round down or round up?


AVG, are you saying that all the ships in campaign are set to even speeds? I asked this question in a long ago thread and I could be mistaken, but I think it was lurker or possibly Ducimus, (whomever it was I trusted) answered that some ships do indeed have speeds set ingame other than whole numbers. I would say if you calculate speed at 7.5 knots, that is what you should enter. It DOES make a difference. I edited my post a bit, so look above and try this experiment for yourself, it's easy to confirm. I'll try to find the thread I'm speaking of.

Rockin Robbins
02-11-09, 05:25 PM
I believe that either tater or Ducimus about a year ago spilled the beans that targets in SH4 move only at whole number speeds. If that's true, all the x½ knot speeds we've been finding haven't hurt a bit!

Soundman
02-11-09, 05:56 PM
Well, I've PM'd Lurker and asked him the question. I'm gonna have egg on my face if I'm wrong!:oops: I have got to say I may wind up in denial, because too many times I've painstakingly measured time over long distances and used a calculator to find say, a 7.5 knot speed and when entering this solution, hit exactly where I aimed. My experience just does not support this therory of whole number speeds. :hmmm: I might add, that if you have played with the mission editor, you will find you can set boats speed at fine fractions, so why not in the campaign?

Soundman
02-11-09, 06:23 PM
Well, I've PM'd Lurker and asked him the question. I'm gonna have egg on my face if I'm wrong!:oops: I have got to say I may wind up in denial, because too many times I've painstakingly measured time over long distances and used a calculator to find say, a 7.5 knot speed and when entering this solution, hit exactly where I aimed. My experience just does not support this therory of whole number speeds. :hmmm: I might add, that if you have played with the mission editor, you will find you can set boats speed at fine fractions, so why not in the campaign?

Lurker has answered the PM. Here is the answer quoted...

"Yes, it depends on how the ships track is programed into the campaign layers. I have used speeds that are not "even" on more than one occasion"


So we can be assured, with RSRDC at least, that we are not wasting our time and effort accurately calculating and entering "Fractions of Knots". :D

AVGWarhawk
02-11-09, 07:02 PM
Good to know!:D

I'm goin' down
02-12-09, 12:06 AM
soundman, what is a "lubberline"? I have a blubberline, but I do not know what a lubberline is?

I'm goin' down
02-12-09, 02:02 AM
Well, I've PM'd Lurker and asked him the question. I'm gonna have egg on my face if I'm wrong!:oops: I have got to say I may wind up in denial, because too many times I've painstakingly measured time over long distances and used a calculator to find say, a 7.5 knot speed and when entering this solution, hit exactly where I aimed. My experience just does not support this therory of whole number speeds. :hmmm: I might add, that if you have played with the mission editor, you will find you can set boats speed at fine fractions, so why not in the campaign?

Lurker has answered the PM. Here is the answer quoted...

"Yes, it depends on how the ships track is programed into the campaign layers. I have used speeds that are not "even" on more than one occasion"


So we can be assured, with RSRDC at least, that we are not wasting our time and effort accurately calculating and entering "Fractions of Knots". :D

I am confused. Lurker says fraction of knots is feasible and you say it is not in RSRDC? Straighten me out if you can?

jazzabilly
02-12-09, 03:34 AM
Not sure about your target's speed down to the "n"th degree?

That's what fan shots are for. Espec. when you must sink that special ship.

Soundman
02-12-09, 09:42 AM
soundman, what is a "lubberline"? I have a blubberline, but I do not know what a lubberline is?

The "Lubber Line" is the line running down the center of the scope. As for Lurkers statement and RSRDC, what I said was we are NOT wasting our time calculating speed down to the fraction. RSRDC implements boats traveling at speeds other than even numbers.



Not sure about your target's speed down to the "n"th degree?

That's what fan shots are for. Espec. when you must sink that special ship.


Jazzabilly, I beleive your missing the point here. The point is, precision shooting takes precision calculations. If you want to estimate, that's your option. I myself would rather put a small merchant down reliably with one shot dead center, than "guess" and feel the need to fire two shots because I'm not sure of the speed or my solution. Of course spread shots are useful, but the "O'Kane" method, is designed to fire as the "Juicy" parts of the ship pass the lubber line. If your solution is not as accurate as it could be, there is a good chance your going to miss the Juicy parts. I realize some people are happy to settle for "close enough", and that's their perogitive, but like I said, I guess I'm a perfectionist and don't feel precision to be a waste of time as some might suggest. Try it for yourself and see. :)

AVGWarhawk
02-12-09, 10:14 AM
Well, I've PM'd Lurker and asked him the question. I'm gonna have egg on my face if I'm wrong!:oops: I have got to say I may wind up in denial, because too many times I've painstakingly measured time over long distances and used a calculator to find say, a 7.5 knot speed and when entering this solution, hit exactly where I aimed. My experience just does not support this therory of whole number speeds. :hmmm: I might add, that if you have played with the mission editor, you will find you can set boats speed at fine fractions, so why not in the campaign?
Lurker has answered the PM. Here is the answer quoted...

"Yes, it depends on how the ships track is programed into the campaign layers. I have used speeds that are not "even" on more than one occasion"


So we can be assured, with RSRDC at least, that we are not wasting our time and effort accurately calculating and entering "Fractions of Knots". :D
I am confused. Lurker says fraction of knots is feasible and you say it is not in RSRDC? Straighten me out if you can?

Lurker says he has made some ships in fractions of a knot. In short, yes, in RSRD some ships can be making .5 of a knot.

I'm goin' down
02-14-09, 07:07 AM
:D I got it. :yeah: