View Full Version : Point of interception

03-27-2005, 06:54 AM
Dose anye one have formula to calculate the distance that a merchet makes. It would make it more esay to calculate the point of interception.

Happy Hunting hehe http://forums.ubi.com/images/smilies/784.gif

03-27-2005, 07:19 AM
Distance simply equals speed multiplied by time, you just need to get the units right.

One nautical mile equals 1.852 km, so a merchant sailing at one knot (nautical mile per hour) will travel 1.85km in an hour. A merchant travelling at ten knots will travel 18.5km, and so on.

03-27-2005, 07:34 AM
From what I've seen so far in the game, anything up to and including 7 knots is listed as SLOW. 8 knots is MEDIUM. I'm guessing that 15 knots is the trigger point for FAST, but I don't know for sure. I've seen a ship going 14 knots listed as medium, and a ship going 18 knots listed as fast, but the switch point could be 15, 16, 17 or 18 knots.

If I'm interecepting a merchant and all I have is the slow/medium report, I assume 7 knots for slow and 12 knots for medium. It seems to work well. The smaller merchants have a max speed of 9 knots, while the larger ones might make up to about 16. I have seen C2/C3 cargo ships and T2/T3 tankers clipping along solo at 12 knots, so thats where I am getting the figure.

03-27-2005, 08:42 AM
Thanks those figures can be realey god to have

03-27-2005, 12:14 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Antesdhlm:
Dose anye one have formula to calculate the distance that a merchet makes. It would make it more esay to calculate the point of interception.

Happy Hunting hehe http://forums.ubi.com/images/smilies/784.gif <HR></BLOCKQUOTE>The problems with trying to calculate a direct intercept is that you don't have the exact speed of the target. So you make your best guess, calculate your course, arrive at the anticipated intercept point and find...nothing. In which direction do you look now?

Try this solution out:

1) When you receive an intercept report layout the target course using the ruler tool. Do this at a moderate level of zoom so that the drawn line is as close to the center of the target as possible (in reduced visiblity a small variance from the center can mean you miss the target).

2) Using the reported speed (RANGE) of the target plot a course that will intercept the track line of the target AHEAD of the target. When you arrive on the track line, as long as the target has maintained that course, you are now directly in it's path.

3) Change course to take you directly down the track line. You should spot your target with sufficient range to allow you to dive and manuver into a perfect position for attack.

The major exception to this tactic is when you are working close inshore. For instance, a convoy entering the straights between the north coast of Ireland and England will usually make a change of course to the SSE once it's entered the straight. Once you get that close inshore, without any new target updates, it becomes more a matter of best guess.

03-27-2005, 12:29 PM
Turn your boat until the target's (absolute) bearing doesn't change.
Then you'll either be going straight towards or straight away from it.

03-27-2005, 12:31 PM
Check my website Antesdhlm.

It has lots of usefull tutorials and a wicked graph you can print out that was put up by a member from simHQ just for that purpose http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

03-28-2005, 12:09 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by jeroen-79:
Turn your boat until the target's (absolute) bearing doesn't change.
Then you'll either be going straight towards or straight away from it. <HR></BLOCKQUOTE>

One might also be at the same course and speed as the target ...

03-28-2005, 12:39 PM
Here is another method that is based on what all the others have said. assume slow is 5 medium is 10 fast is 15 and the top speed they goint at is 20.

Ok so ya get a red blip that says Medium at 2021 .. the time. when you first see a red blip ya want to go for immediatelly put time at 1x I like to click on p pause game then click on + to make it 1. Ok now click on your rudder to aim in front of target and put your speed all the way up.. I'm assuming your on surface.

Let's say you can go 16 .. the red blip says medium so lets assume its going 10. this means that roughly when it goes 20 ruler units you go 30. If it is going 10kts and you are going 10kts then when it goes 20 ruler units you go 20 .. Right? right. .. Ruler units click on the ruler and click on the red blip stretch out ruler in direction the red blip is going. Stetch it out to say 20. I like to first click behind the blip and to initially draw a line through the line showing its direction to more accuratelly show its path. Then I click off to side of path and MIDDLE of the blip and drag ruler out 20 for example and then say ok if I goes 10 knots and since its going medium 10kts then when it goes 20 units .. ruler units.. you go 20 ruler units. If, If your going the same speed in this example 10knots. See if you can intersect it AHEAD of its path .. about 10 Ruler units or so ahead of where you think it will be along its path .. direction .. you have calculated .. when you get to the location that you have calculated in front of its path. But ya gotta most always be going faster than the red blip. Lets say its going medium ( 10 kts )and your going 15 This means when it goes 20 you go 20 Plus Half of whatever you measured out .. Since you measured out 20 you go an additional 10 for every 20 it goes .. meaning when it goes 20 you go 30 units. It is going 10 kts you are going 15 kts .. so when it goes (forget how long it takes) but for explanation in one hour say if it is going 10 miles per hour since you are going 15 miles per hour this means if you measure out say for example 10 miles .. It will go 10 miles in one hour and you will go 15 miles in one hour. But actually this thing is measured in kts and I dont know what the ruler distances mean as far as what 10 units of ruler distance is called but the jargon is not important What Is Important is that it is going Medium so assume that is 10 and lets say you are able to go 15 at either standard speed or full speed or whatever any way your going 15 .. So when you measure out for example 50 ruler units it means that when it goes those 50 units you will go 75 units of ruler distance. Because you are NOT going twice as fast but YOU ARE going 1.5 or one and a half as fast. It it was going slow .. 5 and you were going twice as fast 10 then when it went 10 units you would go 20 units .. I hope at this point ya got the units down as far as how far you go as to how far it goes ..

Ok so now intersect it when ya can .. according to its initial position and your intersect it at a point that you definitelly know is a head of its path. Now the further you are initially from it and whehter or not it is going 10 if it says medium speed it may be going 8 or 9 or 11 or 12 but your going say 16 .. So your calculations may not be exact this is why you make sure you intersect it somewhere ahead of its path. now as mentioned earlier once your definitelly ahead of it turn to move directly up its path head straight towards it .. this is assuming you are directly in its path .. according to how accuratelly you measured out it original angle of movement. Ok so now what I like to do once i am ahead of it is to move back up its path but AT the same time once doing this to submerge AND Rig for silent running this allows you to hear it way before ya see it. And according to the gray blip ya get you then adjust your direction accordingly to intercept it. And when seeing its blip you should be able to know its basic angle of movement in regards to its blip direction because you originally saw its angle of movement as a red blip on map.

03-28-2005, 03:17 PM
I found the best thing is to 'guess' the destination of the ship - if you've got one in the AL sector, then it's most likely headed for Glasgow, if it's south of Ireland most likely Liverpool or Bristol. This is also indicated by the bearing of the contact report. It seems that many ships, even solo tend to follow shipping lanes.

Once you figured out where they roughly run, you can place yourself on the lane (I prefer to lie in wait in front of a target, especially if its a convoy) and let them come to me.

Whenever I see a contact either running slow or medium speed, I set myself in the path of the contact (of course at some distance in front of the sighting) and wait. After a while you get the hang of how angle you need to actually land in front of them...

03-28-2005, 03:31 PM
Slow speed is 6 knots or less. Medium is 7 knots or greater. I haven't been able to find out yet what the top range is for medium since I have yet to come across a "fast" target yet.