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Old 03-17-14, 06:37 PM   #1
THEBERBSTER
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Default What Type Of Bearing Am I Being Given?

What type of bearing does the 'Sonar Man' give?

Does anyone give a true bearing?

Hydrophone Follow Nearest Contact Fix for NewUi 7_1_0 to 7_5_0 mod is this changing the bearing type?
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Old 03-18-14, 04:57 AM   #2
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Default Sonar reports

The reports are based on 0zero being right ahead of the boat. Ninety is to the right, or starboard. A bearing of 270 is left, or port side.

The same is true for the deck watch & lookouts.

Bearings are not the same as headings, which deal with courses or the direction a ship is moving in. A heading of 90 means East.

Best regards, and happy hunting.
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Old 03-18-14, 06:08 AM   #3
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If I have got it right your telling me it is a 'True' bearing. Thank you.
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Old 03-18-14, 07:15 AM   #4
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No,contact reports always provide a relative bearing. A true bearing would be a bearing WRT true North being zero degrees. This has nothing to do with heading, which is the direction a ship is moving WRT true North equals zero degrees..

A target is sighted bearing 090. This bearing is RELATIVE, so the target is directly on the sub's starboard beam. (To the landlubber's right!) The sub's HEADING is 335. so the target bears 045 TRUE. To plot the target's position on the nav chart, you will need the TRUE bearing, because the nav tools are always aligned to true North. Incidently, the target might be HEADING 180 (or anything else). Heading and bearing are in no way related.

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Old 03-18-14, 10:47 AM   #5
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Just to add a little to BigWalleye's excellent explanation, it might help to remember that the soundman has absolutely no idea which way the boat is heading, so his readings by nature have to be relative and not true. The deck watch might have a little better idea due to the position of the sun, or if land is in sight, but again his job is to tell the watch officer the direction relative to the boat. This makes it much quicker and easier for the WO or the captain to know exactly where to look. 'True' bearings are nice for a map, but to the captain in the control room or especially on the bridge the map is the last thing he needs to look at when a target is announced.
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Old 03-18-14, 11:44 AM   #6
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Thank you Steve. I was able to explain "what" pretty well, but your explanation of "why" was quick and clear - obviously drawn from experience.
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Old 03-18-14, 11:52 AM   #7
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"the soundman has absolutely no idea which way the boat is heading"

He should, one ring on the sonar shows relative bearing, the other is slaved to the gyrocompass and shows true bearing with the boat's heading at the top. Most European Navies in WWII used "RED 90" for port beam and "GREEN 90" for starboard beam which was a lot less confusing than 270 relative for port and 090 relative for starboard. OTOH I've met sailors 6 months out of boot camp who still didn't understand the starboard side was relative to the ship's head, and if Bob the Bosun turned around to face aft it didn't swap sides just to stay on HIS right side. Yeah, some sailors really ARE that stupid.

Simplest way to find true bearing after getting a relative bearing report is to look at the sonar, but turn the periscope or TBT (UZO) to the reported bearing and you'll be looking the direction of whatever is reported. Just be thankful the game only models relative and true bearings, and not magnetic bearings, so you don't have to screw around with compass variation math and trying to remember what the hell Can Ducks Make Vertical Turns applies to.
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Old 03-18-14, 11:54 AM   #8
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Have I got this wrong ? 90 + 335 = 425 - 360 = 65 True ?

BigWalleye calculated 45 !
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Old 03-18-14, 12:05 PM   #9
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Quote:
Originally Posted by THEBERBSTER View Post
Have I got this wrong ? 90 + 335 = 425 - 360 = 65 True ?

BigWalleye calculated 45 !
I think he was testing the forum.... congratulations you passed! Think he was thinking 315.

On the subject of the thread, is there a basic seamanship sticky anywhere? Might help out the uninitiated.
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Old 03-18-14, 12:14 PM   #10
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I don't have SH5, but since SH1 through SH3 had something similar I suspect the sonar display works the same. This is from SH4;



Top is always 0, since the ship's head is zero and all relative bearings are a 360 degree compass from that reference point. The inner ring is a gyro compass repeater to show true bearings. Looking under the zero in the outer ring I see 335, that's the sub's true heading. Lookout reports sighting bearing 090, look at 090 on the outer ring, lined up with that on the inner ring is 065 true. No math.
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Old 03-18-14, 02:43 PM   #11
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Quote:
Originally Posted by THEBERBSTER View Post
Have I got this wrong ? 90 + 335 = 425 - 360 = 65 True ?

BigWalleye calculated 45 !
"The proof is left as an exercise for the reader."
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Old 03-18-14, 05:26 PM   #12
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Hey Guys

This is brilliant, true education. (Sorry about the pun)
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