Identifying Ships

[Macgregor the Hammer]

Being stealth hunters, night is the optimum time for an attack. I have a hell of a time identifying a target at night. I've tried changing the gamma, but it ends up with a washed out looking image.

I usually end up with 2-3 choices of ships. Range and AoB are pretty easy to calculate. They are, for the most part not dependent on the ship type. Speed is the variable that I get stuck on and it's one of the most important. It's also where my shot misses the most. Without a correct ship length, I really can't get a solid speed.

If any of you have any tricks or techniques, I'd love to hear them.

Thanks,
MacGregor

[bstanko6]

If it becomes too difficult identifying a ship, pick the one with a mast height in the middle (according to your situation).

If that is impossible, I use a simple rule of using 30m as a mast height for all ships I cannot identify. It’s just right for calculating, and worst case scenario, your timing will be off on torpedo impact.

Let me know how that works.

[Macgregor the Hammer]

Originally Posted by bstanko6

If it becomes too difficult identifying a ship, pick the one with a mast height in the middle (according to your situation).

If that is impossible, I use a simple rule of using 30m as a mast height for all ships I cannot identify. It’s just right for calculating, and worst case scenario, your timing will be off on torpedo impact.

Let me know how that works.

Thanks Skipper.

I'm going to need to work with it. I might have to bite the bullet and turn 'Map Contacts' back on.

[derstosstrupp]

Do what the real skippers did at night and match course and speed. No one EVER needs the rec manual. Not historical to use anyway - their manuals didn’t deliver perfect data. The more you can wean yourself off of reliance on the rec manual, the better you will become.

You might not see details of the ship, but you can see how big it is in terms of how many marks it takes up horizontally or vertically in the binos or UZO, and you can determine relative motion.

So you have 2 options:

Option 1. Spend 15 min or so adjusting your own course and speed until a) the bearing stops moving and b) the target’s size in the optics appears the same. If he’s not getting any closer or further, and not moving ahead or falling behind, you’ve matched course and speed. Notice we don’t care about range as a quantity, only whether he’s growing or shrinking.

Option 2. Adjust course and speed until the bearing stops moving. Assuming you can accurately estimate an AOB, calculate the speed as -

Own speed x sin(constant bearing) / sin(AOB) = target speed

OR.... Use the reverse side of the attack disc if you don’t want to use a calculator:

Align ownspeed with the AOB on the outer red ring, and read off target speed at the bearing on the outer red ring.

[Macgregor the Hammer]

Originally Posted by derstosstrupp

Do what the real skippers did at night and match course and speed. No one EVER needs the rec manual. Not historical to use anyway - their manuals didn’t deliver perfect data. The more you can wean yourself off of reliance on the rec manual, the better you will become.

You might not see details of the ship, but you can see how big it is in terms of how many marks it takes up horizontally or vertically in the binos or UZO, and you can determine relative motion.

So you have 2 options:

Option 1. Spend 15 min or so adjusting your own course and speed until a) the bearing stops moving and b) the target’s size in the optics appears the same. If he’s not getting any closer or further, and not moving ahead or falling behind, you’ve matched course and speed. Notice we don’t care about range as a quantity, only whether he’s growing or shrinking.

Option 2. Adjust course and speed until the bearing stops moving. Assuming you can accurately estimate an AOB, calculate the speed as -

Own speed x sin(constant bearing) / sin(AOB) = target speed

OR.... Use the reverse side of the attack disc if you don’t want to use a calculator:

Align ownspeed with the AOB on the outer red ring, and read off target speed at the bearing on the outer red ring.

This is quite the library of some very useful and applicable information. Thanks very much!!
You planned my weekend for me. I have a lot of reading and notes to write!

MacGregor

[Macgregor the Hammer]

I have read through a considerable amount of the material you shared and it has made it’s way into my Captain’s Book. Thanks again!

I doubt if I will give up using the reference book. I disagree with your assessment of the use of the Reference Book. I’ve seen a considerable amount of pictures of both German and American Captain’s with the reference book in their hands, looking through the periscope. We all have read books about submarine warfare in WW 2 and the one’s I’ve read discuss the use of the reference book. The Office of Naval Intelligence rated the confidence of each image and it’s dimensions . The ONI was constantly updating it as new information became available. The German Abwehr did the same. Disinformation was created on both sides by camouflaging mast height. A great deal of money was spent on developing the stadimeter, precision telemeters, the RAOBF, the omnimeter, the attack disc, target data computers, etc to just be part of the scenery in a sub. The tools are useless without ship data.

The Reference Book is not the end all and be all, just one of many important tools available to a sub skipper.