Dangerous Waters Tutorial 3: Periscope

[@SubBrief]

a reciprocal bearing can be determined by the 'Up 2, Down 2' rule of thumb. example, bearing 050, reciprocal is 230. First digit is +2, so 0+2=2, Second digit is -2, so 5-2=3. 050 becomes 230.

[@M0N0K0I]

Wonderful! Thank you for keeping these rare guides online!!

[@FPSchazly]

You're welcome! I'm a visual person so these guides are as much for me as they are for everyone :)

[@Lymanity]

This is super helpful, especially for Silent Hunter where you pretty much only have hydrophones/sonar and periscope for most of the game.

[@Beskhuepnm]

Expressed as single equations, the course approximation is: (bearing + 180 + port angle on bow) modulo 360; or (bearing + 180 - starboard angle on bow) modulo 360. So for this case: (142 + 180 + 145) modulo 360 = 467 modulo 360 = 107. See it as rotating the target ship's course along the bearing circle, and normalizing the bearing degree only after having done the calculations. Note that the 180 term to calculate reciprocal is required because with an angle on bow of 180 port (or starboard), the ship is heading directly away from us in line with our periscope bearing, and so we'd get that their course is: (bearing + 180 + 180) modulo 360 = (bearing + 360) modulo 360 = bearing

[@Tamburello_1994]

Glad you're doing these tutorials. Waiting for the TMA lesson

[@hafhdrn]

Might wanna add this as an annotation or something, idk - the easiest way to describe AOB is what the enemy watch would call out if they saw you; the bearing of your sub relative to their ship.

[@FPSchazly]

***** that's a great way to think of it!

[@hafhdrn]

***** c: learnt it waaaay back when I first played silent hunter. Stuck with me since.

[@Optimusx1]

although high frequency sonar can be detected IRL, it's not modeled in Dangerous Waters. So no counter detection. It's funny using it as a view screen on track and trail missions!

[@crossfirerambo]

Hey, to help you out with your range estimation (2 ways). Take height given from waterline to masthead and convert to inches. divide that number by its height in mils (hash marks on your scope) and multiply by 27.78 to achieve range in yards. Or you could be lazy like me and look up "Table 15 - Distance by Vertical Angle (Between Horizon and Top of Object)". Convert your mils to MOA (multiply by 3.4377) and use the table to find your range. This is all out of bowditch Vol 2 which also comes with a bunch of other tables that I think you could find super helpful such as; Distance by 2 bearings, height of eye, speed table for measured mile, Speed distance time table, geographic luminous and visual range table(also range but kinda sorta) and a crap ton of other math.

[@FPSchazly]

sounds useful! at what zoom level should the mil height be measured?

[@crossfirerambo]

FPSchazly the less zoom the more mils you should have. you'd have to read into it. on some optics the scope adjusts for it and some don't. you'll have to see visually to determine if it does or doesn't.

[@FPSchazly]

roger that. the improved Kilo optics may be able to do that, but I think the other periscopes have the same mils regardless of zoom

[@crossfirerambo]

let me know if it works. it does in real life ive done it while on watch but im curious about it in the game

[@johanntserclaesgrafvontill7148]

nice vid but is it possible that the range calculation is sometimes incorrect because you have not lined up the horizontal line of the periscope with the waterline of the ship? - just an idea

[@FPSchazly]

Lepi Mica It's possible, but I don't think it should make a difference. The height of the ship is a constant no matter where that horizontal line is, so when you slide one side of the picture, it should always be moving the same amount.

[@johanntserclaesgrafvontill7148]

***** Well it was just an idea ^^ I thought something would go wrong with the trigonometric calculation if its not the waterline but I am not sure since I bought the game yesterday :P Anyway your tutorials helped me a lot

[@FPSchazly]

Lepi Mica Haha, sorry, I didn't mean to come across as mean if I did. Glad they've helped and glad to hear it!

[@sergeylukin8740]

For those who struggle to understand the "If contact has port aspect" sentence like I did initially, it simply means "if you can see vessel's left side". Ships use "port" and "starboard" instead of "left" and "right". Hope that helps.

[@pavelvolkov6145]

Thank you!

[@FPSchazly]

you are quite welcome!

[@slothes6767]

Can you join the Navy in the US if you're colorblind? I know you can't in New Zealand. Just curious :)

[@FPSchazly]

yeah, but you can't do anything "cool" with it, but I wouldn't want to join anyway lol

[@RM97800]

Damn, I play a lot Silent Hunter 3 and I find it baffling that solution calculation using periscope has, in all fairness, degraded after ww2. Germans had all those fancy charts and really nifty discs that do all the math and visualize the data for you (mainly RAOBF and Attack Disc). Here you're back to using basic and inaccurate stadimeter and measuring AOB by eye using reference chart.

[@FPSchazly]

The fancy stuff I'm sure still exists, this game is more realistic than anything else modern out there but it is also still quite simplified. But you're supposed to be able to use sonar and TMA to build solutions over the periscope

[@Qwerty-tr3jk]

could the range problem be that you cannot use the radar mast bit so you have to use the actual bridge for it? just a thought

[@FPSchazly]

+Qwerty192865 without having tried it, here's some actual language from the manual: "4. Click the side of the photo containing the contact’s highest mast and drag that side of the photo such that the top of the highest mast is even with the waterline on the other half of the photo. The estimated range to the ship is displayed in the Range readout."

[@Qwerty-tr3jk]

+FPSchazly oh ok i hadn't read the manual very carefully

[@dixievfd55]

Sad that they don't model helos and surface ships detecting your periscope on radar.

[@FPSchazly]

they do in the Reinforce Alert mod, you have to be within 1 or 1.5 nmi