Sonar and radar

[armatata]

Hi guys, I have recently decided to increase the difficulty level of the game, by installing tmo and rsrd to my sh4. The amount of ship traffic is greatly reduced and I like it. But I have big problems with finding ships because of that. That's why I need some tips, on how to use Sonar, radar and possibly other tools, because I don't really know how.

When I'm out in the open sea and go to sonar, I just hear the wind when I spin it around. However, I constantly get very distant noises which barely are hearable because of the wind. These noises sound like drums. Does anyone else get these? Do they actually mean there is a ship in this direction, just very far away?

Thanks for help!

[SilentPrey]

armatata,

Here's my experience running TMO, RSRDC, and a few others.

If the green light comes on, there is a ship that way. If it doesn't, there is not. (Keep in mind, the green light between 170 and 190 is your ship.) That's the only way I've found the sonar to detect ships. As for radar; that's a bit more sporadic with its detection. However, signals detected are always bright. There will not be any slight changes on the radar screen either.

My advice: Just do more patrolling. Try to find natural choke points and position yourself directly between ports that will probably have traffic.

Fair winds and following seas,
SilentPrey

[gutted]

Note:
There's a bug/issue with the hydrophone that if a ship is doing less than half it's max speed, you wont hear it on the hydrophone.

[fireftr18]

When you hear a ship on sonar, it will be an unmistakable, rhythmical prop noise. When you have time compression high enough for the stop watch to come up, you will notice an occasional lag in the screen rate. That happens when a contact is close enough for you to hear on the sonar, but your sonar man won't "notice" it. Many of us consider that as a time compression feature to identify when a target is close.

Good hunting.

[mikesn9]

From Gutted
Note: There's a bug/issue with the hydrophone that if a ship is doing less than half it's max speed, you wont hear it on the hydrophone.

Aha! That explains some things.. I have that happen at times. Pick up a ship on radar, set up, and even when it's close : no sonar detection. And that means: No hydrophone detection, no sonar ranging possible.

1.5 stock here, is it fixed in any Mods?

[CapnScurvy]

The issue of the non existent Hydrophone sound is for manual player use only. The sonar man usually reports the sound, but you won't hear a thing when you go to listen for it yourself.

Actually, the stock game has the best chance in not having this Hydrophone issue. Mods that have their own Campaign missions usually set the ships traveling speeds differently than stock. Most stock merchants travel about 8 to 9 knots...throughout the ships route from spawn to end. With a merchant ship that has its "MaxSpeed=" in its .sim file, set at 16 knots.....a 9 knot travel speed will be heard just fine. A mod that decides to lower the travel speed below the half MaxSpeed figure will usually result in the ship never being heard.

Some mods switch the travel speed on every waypoint....with dozens of additional waypoints along its route. Many times more waypoints than the stock game's. The idea was sound to do this, thinking more waypoints, with constant changing speeds, would make for a more difficult firing solution, but it just adds to the frustration of not hearing a ship while using the Hydrophone when its easily in sight.

[LittleGrebe]

Originally Posted by armatata

(...)

When I'm out in the open sea and go to sonar, I just hear the wind when I spin it around. However, I constantly get very distant noises which barely are hearable because of the wind. These noises sound like drums. Does anyone else get these? Do they actually mean there is a ship in this direction, just very far away?

Thanks for help!

Sometimes, your sonar man is tired, lazy, delusional or planning a mutiny, so you have to listen for yourself.

Set the speakers to maximum level and you can hear the distant thumping sound of a merchant between the singing whales, long before your sonarman reports it.

As others already mentioned, the opposite is more common.

[Zero Niner]

Here's a weird "feature": I was surfaced, running at about 9 kts in a P=class. Then the sonarman calls out contacts and I see a few grey and blue lines. It was an enemy convoy, and I was still surfaced.
I'm no naval person but surely passive sonar doesn't work when surfaced?

I'm using GFO 1.1.

[fireftr18]

Originally Posted by Zero Niner

Here's a weird "feature": I was surfaced, running at about 9 kts in a P=class. Then the sonarman calls out contacts and I see a few grey and blue lines. It was an enemy convoy, and I was still surfaced.
I'm no naval person but surely passive sonar doesn't work when surfaced?

I'm using GFO 1.1.

It depends on the sonar set you have. I'm not sure about the P-Class. The sonar set of fleet boats had a head on the bottom of the hull so that passive sonar is useful while on the surface.

[propbeanie]

The Porpoise did too, but they are just a ~pinch~ overly sensitive. You really shouldn't be able to hear much at 9 knots besides the noise your hull makes going through the ocean, but oh well... The watch crew will make up for it here in just a little bit probably...

[CapnScurvy]

Originally Posted by Zero Niner

Here's a weird "feature": I was surfaced, running at about 9 kts in a P=class. Then the sonarman calls out contacts and I see a few grey and blue lines. It was an enemy convoy, and I was still surfaced.
I'm no naval person but surely passive sonar doesn't work when surfaced?

I'm using GFO 1.1.

If the mod is designed correctly, there is no reason for a newer American sub to not detect a target while surfaced. Unlike the German U-Boat's, most later U.S. Fleetboats had their Sonar/Hydrophone equipment on the bottom of the hull:





The Germans (and the earlier American class subs) had their equipment on the deck....requiring the sub to be submerged in order to operate. Here's an S-Class subs Hydrophone receiver:




An early Porpoise Hydrophone receiver:




Later in the war, the Porpoise and other early sub classes got the hull mount versions, allowing surfaced reception. The only drawback was the already mentioned interference from the subs own speed that created issues for the equipment. A 9knt speed should not produce detection. However, a surfaced American sub, at the correct time period....at a lower speed, will work.

I'm planning on making sure the Sonar/Hydrophones work as expected for the different subs with the FOTRS Ultimate mod. I'm even going to add the ability to have an S-Class boat purchase, through an upgrade, a Hull Mount receiver...probably towards the later stages of the subs life cycle.

[max-peck]

Originally Posted by CapnScurvy

An early Porpoise Hydrophone receiver:

Oh so that's what that is.

I knew about the S Boats having a deck mounted hydrophone receiver
But I did not know the early war Porpoise Boats also had one

I tend to start all of my careers in early 1942 in a Porpoise, and always wondered what that thing on my deck was
I just never made the connection.

Good info - thanks Capn

[Zero Niner]

I have another question: I have the option of installing the SJ or SJ-I radar on my boat. I suppose the SJ-I is an improved version of the SJ?

[CapnScurvy]

Originally Posted by Zero Niner

I have another question: I have the option of installing the SJ or SJ-I radar on my boat. I suppose the SJ-I is an improved version of the SJ?

Yes, the SJ-I usually has greater detection capabilities (greater maximum range, better detection probability). Least it should with most mods and the stock game. But, there are mods that don't address the Radar at all....without giving much thought in accuracy, or authentic characteristics.

It's like the early subs that should only produce hydrophone use while your submerged. Some of them don't do that. You'll get hydrophone use no matter which position your sub is in (besides the reason of not getting it while the target is traveling at less than half its MaxSpeed). It's all kind of confusing for a player who doesn't know what to expect, yet knows what the game does, and believes the behavior is normal.