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washishu · 10-17-10, 11:39 AM

I have not visited the forums for some time. To ddiplock—can't remember where I got the information from but I did once hear that the physics and sonar modeling in Sub Command is very accurate. Maybe, maybe not, who can say? However, from my limited reading around the subject I think the problem lies with Hollywood! The submarine movies would have us believe that sonar is capable of detecting and identifying a vessel from one side of the ocean to the other and hear someone using an electric toothbrush 20 miles away. Nonsense.

The more information you have about a contact (this usually means being closer and/or listening for longer) the more accurate the classification will be, It's also affected by water conditions (these are set up by whoever creates the mission and determine how sound will travel through the water).

Given that we are not physicists and it IS only a game we have to take some things for granted. The "list" of possible classifications you get in the narrowband will get shorter as you get more information about the contact. You can also use your own judgment—that is, what are you expecting? Is it likely that this contact is what you are looking for?

It does seem that the autocrew are much more sensitive than you can ever be; that is, they can detect very slight blips that you won't recognise as possible contacts. But they can also get it wrong. You might find that the autocrew classifies a contact as one thing where you know for 100% certain it is something else. Well. it is only a game.

To E.Luden—Silent Hunter used both TRUE and RELATIVE bearings. Zero degrees TRUE is true north (different from magnetic north). Zero degrees RELATIVE is the direction you are pointing; that is, it is always the bows of the vessel, therefore 180 degrees RELATIVE is the stern of the vessel. This practice seems not to be used anymore—don't know why but I suspect that it is connected with electronic navigation systems which are not affected by magnetic variations and are able to keep track of true north no matter which way you are pointing, no matter how you twist and turn. It is more usual now, as I understand things, to use TRUE bearings only. As I remember (without checking) the 'scope stays at whatever bearing it is when you lower it. Therefore, if you have moved around some since you lowered it, when you raise it again it will be on a different bearing. The bearings in the 'scope are TRUE not RELATIVE.

If you play around in the Mission Editor a little, you'll get some notion of how things work. It's a game, it's not real. Enemy subs don't actually "hear" you at all. Detection is determined by the parameters set up by the creator of the mission. If this is set so that if you exceed a speed of (say) 5 knots within (say) 3 miles of an enemy sub you will be detected, then you can (if you know this information), zoom up to the enemy sub at 15 knots until you are 4 miles out, then slow to 4 knots and you won't be detected. The uncertainty lies in how accurate your fix on the enemy sub is and the mission editor has various means to inject this kind of uncertainty into the game.

10-17-10, 11:39 AM	#4
washishu Mate Join Date: Apr 2010 Location: England Posts: 54 Downloads: 2 Uploads: 0	It's a game; a good one but it IS a game I have not visited the forums for some time. To ddiplock—can't remember where I got the information from but I did once hear that the physics and sonar modeling in Sub Command is very accurate. Maybe, maybe not, who can say? However, from my limited reading around the subject I think the problem lies with Hollywood! The submarine movies would have us believe that sonar is capable of detecting and identifying a vessel from one side of the ocean to the other and hear someone using an electric toothbrush 20 miles away. Nonsense. The more information you have about a contact (this usually means being closer and/or listening for longer) the more accurate the classification will be, It's also affected by water conditions (these are set up by whoever creates the mission and determine how sound will travel through the water). Given that we are not physicists and it IS only a game we have to take some things for granted. The "list" of possible classifications you get in the narrowband will get shorter as you get more information about the contact. You can also use your own judgment—that is, what are you expecting? Is it likely that this contact is what you are looking for? It does seem that the autocrew are much more sensitive than you can ever be; that is, they can detect very slight blips that you won't recognise as possible contacts. But they can also get it wrong. You might find that the autocrew classifies a contact as one thing where you know for 100% certain it is something else. Well. it is only a game. To E.Luden—Silent Hunter used both TRUE and RELATIVE bearings. Zero degrees TRUE is true north (different from magnetic north). Zero degrees RELATIVE is the direction you are pointing; that is, it is always the bows of the vessel, therefore 180 degrees RELATIVE is the stern of the vessel. This practice seems not to be used anymore—don't know why but I suspect that it is connected with electronic navigation systems which are not affected by magnetic variations and are able to keep track of true north no matter which way you are pointing, no matter how you twist and turn. It is more usual now, as I understand things, to use TRUE bearings only. As I remember (without checking) the 'scope stays at whatever bearing it is when you lower it. Therefore, if you have moved around some since you lowered it, when you raise it again it will be on a different bearing. The bearings in the 'scope are TRUE not RELATIVE. If you play around in the Mission Editor a little, you'll get some notion of how things work. It's a game, it's not real. Enemy subs don't actually "hear" you at all. Detection is determined by the parameters set up by the creator of the mission. If this is set so that if you exceed a speed of (say) 5 knots within (say) 3 miles of an enemy sub you will be detected, then you can (if you know this information), zoom up to the enemy sub at 15 knots until you are 4 miles out, then slow to 4 knots and you won't be detected. The uncertainty lies in how accurate your fix on the enemy sub is and the mission editor has various means to inject this kind of uncertainty into the game.