Close Encounters?
 

In a recent encounter with another SSN, I detected a single narrow band tonal. As I turned to try to close on the target, in just a few seconds, it turned into a full spectrum and I realized that the target I was tracking was heading straight for me and was MUCH closer than I'd anticipated! The replay revealed that we'd narrowly avoided a collision.

Is there any good way to avoid these types of encounters?

Broadband and demon screens are especially useful for that. Try dropping your NB contact and remarking it from BB. If you have more than 6 lines on demon on another submarine, you're way close, especially if you're both heading right at eachother.


Also you should occasionally use your HF sonar even in blue waters, to check if there are any objects around you such as mines, submarines or debris.

If you are in the Kilo you can use your periscope to check if anything is very close to you, but you have to be shallow for that or you'll flood the scope. :ping:

Of course the most obvious sign that you're too close is an extremely sudden and major bearing aspect change. That's never good. I have had a few of these myself (Usually in the 'quick generated' missions).

Was it a weak signature in your TA or SA?
This is sort of interesting to me. In movies and even in novels the scenario of subs coming extremely close is quite usual. For example in the "Seawolf" novel this vicinity is extreme, the Seawolf is just a few meters from the other sub, and the other sub still didn't detect it.
Now i didn't think that would ever happen in DW, but you're talking of collision danger :rock: . Is this really something that can occour in RL?

What class was the other SSN? How much time did elapse from detection to collision danger?

Me too. It's one of those things I'd read about but never seen in the sim.

Yes, I think so. Even close in, against quiet targets, depending on depth, there are occaisionally places with a great deal of transmission loss, due to the Lloyd mirror effect. US submarines have collided with Soviet submarines in the past. Even in a convergence zone environment this danger might exist because while you have a long CZ range, your direct path range might be quite short, so you don't know exactly where a target is by the time you're close to him. So, sure, it's possible.

It was a TYPHOON class SSBN, and it was maybe 20 seconds or so before I realized what was going on. I was testing my latest revision of the Kara Sea Strategic ASW scenario. We passed well within a nautical mile of each other.

It was interesting, though, because after he zoomed right past me, I had a GREAT Ekelund range from the sphere.:rock:

My big gripe with the "quick generated" scenarios is that they always seem to start me off immediately in front of an iceberg.

Persicope floods only when it is extended at speed over ~8 knots.:yep:

It can be extended at any depth.

@seaquenn
 

Be sure to execute collision avoidance moves once you get a bearing. You may also want to check the HF sonar if you're driving the Seawolf class.

I too have used the scenario generator where the it places an opposing vessel too close. Since I normally drive the Seawolf, I just make it a habit to use the HF sonar. It's quick and so far as I know, it's undetectable.

Good rule of thumb for an initial contact is to wait for the bearing rate and direction. Any contact that is left of your heading with a right bearing rate you ASSUME the contact is closing, and at the very least will cross your LOA (Line of Advance). Left bearing rate is opening. When right of own ships heading, left bearing rate is closing and right bearing rate opening.

Always manuever AWAY from the contact until you know (fairly well) what the contacts range is. This also keeps a narrow band contact from being masked by own ship. Same is true of broadband contacts until you know it's range and course.

This is derived by the fact that own ships speed is closing the contact when contact bearing rates are towards your own heading.

Hope this helps. These assumptions on initial contact saved my bacon (and my shipmates) in the real world.

That was very useful, but there's one thing I'm unclear about. What's to quickly distinguish a slow or distant target from a target on a collision course? Both would exhibit low bearing rates.

The demon display would rule out whether or not it's close and will also give you its speed.

A close contact will have a high bearing rate regardless of the targets speed (or lack of it). If you have a contact with a low or zero bearing rate, reverse course (with a turn AWAY from the contact!). If the contact is close, the bearing rate will increase. And change depth, preferably deeper.

A far contact's bearing rate is almost all due to own ships speed.

Remember, submarine manuevers are three demensional; verticle, horizontal, and SPEED. (As apposed to a skimmer, which is stuck on the surface.)