What does the TDC set?

Waervyn · 12-04-14, 05:32 PM

After watching the excellent tutorials by Stoainm, I managed to track myself a target. Woooo!

Small question though. If we put in the speed of target, bearing, AoB etc...what exactly it left for the TDC to program into the torpedo?
Is it just the angle at which it will fly towards the target?

Also, why would you ever fire a slow torpedo instead of a fast one? Is that in case the target is too close for the torpedo to 'turn' in time?

Sorry for the naive questions! I've been reading up a bit on wiki about TDC's, but the specific answer I couldn't find.

Thanks again!

12-04-14, 06:39 PM

Hey! And welcome to Subsim!!

Learn to get familiar and love your TDC!! It takes all of the math out of a solution, well almost all of it.

At the bottom there should be two dials you cant adjust, if your TDC is not in manual mode (It shouldn't be after you enter your Speed, AOB, and stuff) (OR If you use the Watch Officer Window to set it, either way it works) then the dials at the bottom should turn as you turn your scope, this is called your Gyro Angle. The one on the left is degrees the one on the right is increments of degrees, basically you want those dials to have both of their dial arrows pointing upward, indicating a Gyro Angle of 0. This means that when your scope is there, whatever crosses the crosshairs of your periscope, will be hit right where those crosshairs are aiming. Hope that clears things up!

Any more questions, feel free to ask!!

Waervyn · 12-05-14, 01:32 AM

Thanks!

So the only thing the TDC has to calculate is the angle at which to fire your torpedo's, or alternatively, the 'gyro angle' in order to shoot straight at 90 degrees and still hit your target right?

Sorry for being really 'semantic'...I have this stupid thing that if I don't understand a thing 100% I have the feeling I understand it 0%, even though I might understand it 95% (if that makes sense...drove my teachers MAD years ago!

)

12-06-14, 12:23 AM

Yes kind of. Basically the TDC sets a lead angle for your scope. So if your solution is set to be straight ahead of you, the gyro angle is to the left (or right side depending on which way your target is moving) of your 0 heading, and when it crosses that line you fire. When the target reaches that spot on your scope, it means if you fire the torpedo then, based on what you set in speed for your torpedo, and the ship, they will meet in the exact same spot. That help?

Lanzfeld · 12-06-14, 09:00 AM

Slow torpedo has longer range.

Something like fast=4500 meters, slow=12500 meters.

Not sure if modeled in SH-5.

Steam torpedos only.

Laconic · 12-07-14, 11:59 AM

I also tend to think that slower torpedoes have a higher chance of detonation. That's not confirmed by anything other than anecdotal evidence on my part, but I seem to have fewer duds when I fire slow speed torpedoes.

12-04-14, 05:32 PM	#1
Waervyn Seaman Join Date: Dec 2014 Posts: 32 Downloads: 6 Uploads: 0	What does the TDC set? After watching the excellent tutorials by Stoainm, I managed to track myself a target. Woooo! Small question though. If we put in the speed of target, bearing, AoB etc...what exactly it left for the TDC to program into the torpedo? Is it just the angle at which it will fly towards the target? Also, why would you ever fire a slow torpedo instead of a fast one? Is that in case the target is too close for the torpedo to 'turn' in time? Sorry for the naive questions! I've been reading up a bit on wiki about TDC's, but the specific answer I couldn't find. Thanks again!

12-04-14, 06:39 PM	#2
reignofdeath Stowaway Posts: n/a Downloads: Uploads:	Hey! And welcome to Subsim!! Learn to get familiar and love your TDC!! It takes all of the math out of a solution, well almost all of it. At the bottom there should be two dials you cant adjust, if your TDC is not in manual mode (It shouldn't be after you enter your Speed, AOB, and stuff) (OR If you use the Watch Officer Window to set it, either way it works) then the dials at the bottom should turn as you turn your scope, this is called your Gyro Angle. The one on the left is degrees the one on the right is increments of degrees, basically you want those dials to have both of their dial arrows pointing upward, indicating a Gyro Angle of 0. This means that when your scope is there, whatever crosses the crosshairs of your periscope, will be hit right where those crosshairs are aiming. Hope that clears things up! Any more questions, feel free to ask!!

12-05-14, 01:32 AM	#3
Waervyn Seaman Join Date: Dec 2014 Posts: 32 Downloads: 6 Uploads: 0	Thanks! So the only thing the TDC has to calculate is the angle at which to fire your torpedo's, or alternatively, the 'gyro angle' in order to shoot straight at 90 degrees and still hit your target right? Sorry for being really 'semantic'...I have this stupid thing that if I don't understand a thing 100% I have the feeling I understand it 0%, even though I might understand it 95% (if that makes sense...drove my teachers MAD years ago! )

12-06-14, 12:23 AM	#4
reignofdeath Stowaway Posts: n/a Downloads: Uploads:	Yes kind of. Basically the TDC sets a lead angle for your scope. So if your solution is set to be straight ahead of you, the gyro angle is to the left (or right side depending on which way your target is moving) of your 0 heading, and when it crosses that line you fire. When the target reaches that spot on your scope, it means if you fire the torpedo then, based on what you set in speed for your torpedo, and the ship, they will meet in the exact same spot. That help?

12-06-14, 09:00 AM	#5
Lanzfeld Grey Wolf Join Date: Jan 2002 Location: New Tripoli, PA Posts: 994 Downloads: 64 Uploads: 0	Slow torpedo has longer range. Something like fast=4500 meters, slow=12500 meters. Not sure if modeled in SH-5. Steam torpedos only.

12-07-14, 11:59 AM	#6
Laconic Soundman Join Date: Dec 2007 Posts: 142 Downloads: 109 Uploads: 0	I also tend to think that slower torpedoes have a higher chance of detonation. That's not confirmed by anything other than anecdotal evidence on my part, but I seem to have fewer duds when I fire slow speed torpedoes.