Unites States submarines, the constant bearing firing method, plus part II

stork100 · 06-04-18, 08:02 PM

Thank you very much for these highly detailed and informative posts. Really excellent.

greyrider · 06-05-18, 09:50 AM

thank you Stork, if you have any questions, feel free to ask, and i will help, but if you learn the method, and you shoot in the divergent spread, your actually in elite company.
at the begining of the post, i said it was the most popular method used by submarine captains, i have to take that back now, after rereading a passage from clear the bridge.

reexamining this quote from clear the bridge:

“ Ten degrees to go , ” called Fraz . This would be a new one for me . I could get the “ Constant bearing — mark ” off handily , but the “ Fire ” on a separate exposure might be too early or late . I considered firing on generated bearings , most submarines did , but with only two torpedoes , I’d stick with our bow - and - arrow method . “ Constant bearing . ” Jones raised the scope on the generated bearing . I swung it ahead to amidships and called , “ Mark ! ” Jones dunked the scope and raised it immediately . “ Fire ! ” The mainmast had passed the wire , but the after well deck was still on . The torpedo went out with a whine . The second double dip was more accurate , and our last torpedo was on its way for her foremast , its whine fading out in a few seconds . The range was 900 yards , the gyros near 180 , the same as near zero for a bow shot .

"I considered firing on generated bearings , most submarines did"

captain okane is telling us that most us submarines were firing on the generated firing bearing, if thats the case, then they were firing a longitudinal spread, and not a divergent spread, so if thats true what he said, only a very few u.s. skippers fired the constant bearing method with divergent spreads, okane was one of them. he called it his " bow and arrow method".

stork100 · 06-05-18, 07:58 PM

Very cool. I only got SH4 literally a couple of days ago, but as a veteren of SH3 and manual targeting enthusiast, every bit of information on how they really did it is like gold to me. No doubt O'Kane was the master.

greyrider · 06-06-18, 07:15 PM

your going to be fine here stork, i was over at the sh3 forums when the game came out, so its good to see you here, just the position keeper is the only difference really, sh4 is really sh3 underneath. i have started a german career in sh4, a couple of days ago, so i can work out the constant bearing method with german submarines, and then post it in the sh3 forums, i cant get sh3 to work anymore.

anyway, any questions, feel free to ask.

found a reference to distance to horizon in the torpedo fire control manual,
page 5-6

this

(6) At extreme ranges it must be remembered that the waterline is below the horizon. This necessitates estimating the position of the waterline.

jenrick · 06-30-18, 12:58 PM

So I'm tracking on most of this, however I got lost on a few things.

How is it determined what the range of acceptable shooting angles is? In the example you have I understand determining 339 as the correct angle for an engagement with a longitudinal spread (or a single aimed fish for that matter). However where I got off track was figuring out the spread of bearings one can fire on.

So in your example of the pivot bearing being 18, why is the lower bound 14 degrees and the up bound 21 degrees?

I thought with the TDC engaged it generated a bearing and set the gyro angle for it regardless of where the scope was pointing? So do I need to send a new bearing and range to the TDC with each torpedo?

Also as I only recently re-installed SH4, does this work with stock 1.5 or do I need to add some mods to get things up to snuff?

Thanks!

millnate · 03-15-25, 03:48 PM

Quote:

Originally Posted by jenrick

So I'm tracking on most of this, however I got lost on a few things.

How is it determined what the range of acceptable shooting angles is? In the example you have I understand determining 339 as the correct angle for an engagement with a longitudinal spread (or a single aimed fish for that matter). However where I got off track was figuring out the spread of bearings one can fire on.

So in your example of the pivot bearing being 18, why is the lower bound 14 degrees and the up bound 21 degrees?

I thought with the TDC engaged it generated a bearing and set the gyro angle for it regardless of where the scope was pointing? So do I need to send a new bearing and range to the TDC with each torpedo?

Also as I only recently re-installed SH4, does this work with stock 1.5 or do I need to add some mods to get things up to snuff?

Thanks!

I have this same question. I understand why the shoot bearing is 18, but no idea how he came up with the spread of 7 degrees.

Anyone understand that part?

06-05-18, 09:50 AM	#2
greyrider Watch Officer Join Date: Apr 2005 Location: massachusetts Posts: 334 Downloads: 237 Uploads: 0	thank you Stork, if you have any questions, feel free to ask, and i will help, but if you learn the method, and you shoot in the divergent spread, your actually in elite company. at the begining of the post, i said it was the most popular method used by submarine captains, i have to take that back now, after rereading a passage from clear the bridge. reexamining this quote from clear the bridge: “ Ten degrees to go , ” called Fraz . This would be a new one for me . I could get the “ Constant bearing — mark ” off handily , but the “ Fire ” on a separate exposure might be too early or late . I considered firing on generated bearings , most submarines did , but with only two torpedoes , I’d stick with our bow - and - arrow method . “ Constant bearing . ” Jones raised the scope on the generated bearing . I swung it ahead to amidships and called , “ Mark ! ” Jones dunked the scope and raised it immediately . “ Fire ! ” The mainmast had passed the wire , but the after well deck was still on . The torpedo went out with a whine . The second double dip was more accurate , and our last torpedo was on its way for her foremast , its whine fading out in a few seconds . The range was 900 yards , the gyros near 180 , the same as near zero for a bow shot . "I considered firing on generated bearings , most submarines did" captain okane is telling us that most us submarines were firing on the generated firing bearing, if thats the case, then they were firing a longitudinal spread, and not a divergent spread, so if thats true what he said, only a very few u.s. skippers fired the constant bearing method with divergent spreads, okane was one of them. he called it his " bow and arrow method". __________________ Her gun crew had guts, however, for from her canting bow came a half dozen well-aimed rounds. How they pointed and trained their gun on that tilting platform will long remain a wonder, and their dedication in keeping up the fire until they went under would be a matter of pride to any nation. O'Kane, Richard. Clear the Bridge!: The War Patrols of the U.S.S. Tang

06-06-18, 07:15 PM	#4
greyrider Watch Officer Join Date: Apr 2005 Location: massachusetts Posts: 334 Downloads: 237 Uploads: 0	your going to be fine here stork, i was over at the sh3 forums when the game came out, so its good to see you here, just the position keeper is the only difference really, sh4 is really sh3 underneath. i have started a german career in sh4, a couple of days ago, so i can work out the constant bearing method with german submarines, and then post it in the sh3 forums, i cant get sh3 to work anymore. anyway, any questions, feel free to ask. found a reference to distance to horizon in the torpedo fire control manual, page 5-6 this (6) At extreme ranges it must be remembered that the waterline is below the horizon. This necessitates estimating the position of the waterline. __________________ Her gun crew had guts, however, for from her canting bow came a half dozen well-aimed rounds. How they pointed and trained their gun on that tilting platform will long remain a wonder, and their dedication in keeping up the fire until they went under would be a matter of pride to any nation. O'Kane, Richard. Clear the Bridge!: The War Patrols of the U.S.S. Tang

06-30-18, 12:58 PM	#5
jenrick Bosun Join Date: May 2007 Posts: 64 Downloads: 38 Uploads: 0	So I'm tracking on most of this, however I got lost on a few things. How is it determined what the range of acceptable shooting angles is? In the example you have I understand determining 339 as the correct angle for an engagement with a longitudinal spread (or a single aimed fish for that matter). However where I got off track was figuring out the spread of bearings one can fire on. So in your example of the pivot bearing being 18, why is the lower bound 14 degrees and the up bound 21 degrees? I thought with the TDC engaged it generated a bearing and set the gyro angle for it regardless of where the scope was pointing? So do I need to send a new bearing and range to the TDC with each torpedo? Also as I only recently re-installed SH4, does this work with stock 1.5 or do I need to add some mods to get things up to snuff? Thanks! Last edited by jenrick; 06-30-18 at 01:24 PM.

06-04-18, 08:02 PM	#1
stork100 Weps Join Date: Sep 2017 Location: Australia Posts: 371 Downloads: 92 Uploads: 0	Thank you very much for these highly detailed and informative posts. Really excellent.

06-05-18, 07:58 PM	#3
stork100 Weps Join Date: Sep 2017 Location: Australia Posts: 371 Downloads: 92 Uploads: 0	Very cool. I only got SH4 literally a couple of days ago, but as a veteren of SH3 and manual targeting enthusiast, every bit of information on how they really did it is like gold to me. No doubt O'Kane was the master.