optimum speed for Subs?

steinbeck · 05-12-15, 05:07 PM

Odd that. At one time it was 'ahead standard' the most efficient speed for cruise.
I'll try a new start and cruise at 2/3 although with my older set of mods I was fine to get there and back.

What is meant by ISP?

merc4ulfate · 05-12-15, 06:48 PM

Improved Ship Physics 2.6_TMO_RSRDC_OTC = ISP

I normally run the TMO small patch after TMO and before any other mod ... it will avoid the Terrible T issue.

SilentPrey · 05-13-15, 12:17 AM

Quote:

Originally Posted by merc4ulfate

Improved Ship Physics 2.6_TMO_RSRDC_OTC = ISP

I normally run the TMO small patch after TMO and before any other mod ... it will avoid the Terrible T issue.

Yes. However, the small patch gets overwritten with this configuration. I believe it is OTC. When using the small patch the way you describe I ended up getting 'upgraded' from a Gato to a Tambor. So I incorporated the small patch fix into the OTC_ISP_Crew Mod.

steinbeck · 05-13-15, 11:36 AM

So I wasn't dreaming,that 'Ahead standard' was the best cruising speed!

Anyway, I've adopted the 2/3rds etc and it seems to be ok so far.

Amazing how out of touch one gets after a 5 year absence.

Jusat wish I coulds get SHIII to work on my Win & rig. Installs from my old disk, even bought a new?? one which turned out to have the same problem. Some Microsoft message, but unable to find any solution. Still got my Grey Wolves mods etc . Very disappointing.

Sailor Steve · 05-13-15, 12:14 PM

First question: Is it installed to Program Files? If so, make a folder outside of Program Files and move or install it there. That may or may not solve the problem but it's an accepted problem that newer versions of Windows don't like you putting things there.

I run SH3 on Windows 8.1 with no problems at all.

CaptBones · 05-13-15, 02:28 PM

Not to throw a wrench into the works or dampen anyone's enthusiasm...

But, trying to apply real world logic/facts/figures into the simulations we're playing here is not always particularly useful, really. The SH4 game engine, derived from the SH3 engine, simulates a U-boat mechanical/electrical propulsion drive system. It's not even close to the US "Fleet" boats' diesel-electric drive system...not even in the ballpark, totally incorrect. To start with, those boats not only had four diesel-generator sets for main propulsion, but also from one to three auxiliary/emergency diesel-generator sets that could provide all ship's service electrical power, charge the batteries, or drive the propulsion motors just as well as the main DG sets could, but achieving a much slower speed. Yes, the design performance characteristics are useful in attempting to get the simulated submarines to behave as "realistically" as possible. But even there I would suggest the word "accuracy" is more correct than "realism" (which is something that IMHO applies to everything in the world of computer games/simulations...the "realism" involved in sitting at a computer playing games/simulations is 0%).

One of the comments made about the meaning of the term "Standard Speed" is quite correct. Ships, warships especially, are designed to meet a broad spectrum of specified performance requirements. Standard Speed is exactly that...a speed (with a specific propeller turn-count) to meet tactical maneuvering requirements, including turn-rate, Advance and Transfer, and Tactical Diameter of turns, in order to be able to safely maneuver in a Formation of other ships, including different Types and Classes. In the USN, prior to WWII as well as now, that speed was 15 kts, at "Full Load" displacement, with excess shaft HP to allow for bottom fouling. Making turns for Standard Speed with a clean bottom and/or at "Light Load" displacement, would typically provide for 16-17 knots or possibly even more, depending on weather and sea-state. For the "Fleet" boats, which were designed to operate with the Fleet, the variable of being able to change the ship's surfaced draft was an added dimension that just serves to make the problem in our game engine(s) even more difficult. Preparing for conducting Full Power Trials and Economy Trials always includes correction of the required turn-count based on draft and bottom condition. USN Economy Trials are always run at 15kts "through the water" (as differentiated from "over the ground").

The propulsion plant is designed to provide for "economical" cruising at that same speed. Here, the key is something that also has been mentioned before in this and other threads on SubSim forums. Standard Speed is the "economical" speed for a warship, but does not necessarily mean the most fuel-efficient speed; it's a combination of time and distance. If you are lolly-gagging around taking your merry time to get someplace where you're supposed to be, you'll find yourself being relieved of Command in short order.

Tweaking the game files to achieve 100% "realism" in propulsion plant performance is impossible. It would require a super-computer to do that and that is beyond the financial means of any/all of us...we had one (or two) of those at NAVSEA and used them to make 100% accurate models of ships and ship propulsion plants. Even then, Trials with real ships seldom produced the same results as our simulations. The most powerful computers still can't match Mother Nature's weather and other variables, environmental and man-made.

Anyway...not to throw a wrench into the works or dampen anyone's enthusiasm...we do need to use whatever tricks and tweaks that can be done to ensure that our boats can get to their assigned Patrol/Special Mission areas with enough fuel to complete the mission and get back home again. Whether a needed Mod/tweak increases the fuel capacity to ridiculous amounts or ridiculously improves propulsion plant efficiency probably doesn't matter. I would simply finish by suggesting that nobody get too wrapped up in trying to achieve 100% "realism" or accuracy, because it's never going to happen here.

Oh, there is one other thing. My wish list includes a fix for the incorrect engine orders and the completely incorrect rudder angles. We hear "Ahead Slow" for the Ahead 2/3 engine order telegraph setting. There is no "Ahead Slow" engine order in the USN...Ahead 1/3 is ahead slow (or slow ahead if you prefer). The use of 40 degree "standard" rudder is ridiculous, in any Navy. You're putting the rudder into the stops at 40 degrees, which is a good way to jam the rudder hard over. Depending on the design of the ship and the desired performance characteristics, "Standard" rudder is typically 15-20 degrees; "Full" rudder is usually 25-30 degrees and "Hard" rudder is normally 5 degrees less than putting the ram(s) into the stops. Instead of fixing the hydrodynamic drag for a 40 degree "standard" rudder, couldn't we change the normal rudder angle used to 20-25 degrees (and then tweak the turn rate & etc.)?

Sailor Steve · 05-13-15, 03:29 PM

Quote:

Originally Posted by CaptBones

Not to throw a wrench into the works or dampen anyone's enthusiasm...

Excellent summary of the problems involved in real-world ship command.

Quote:

If you are lolly-gagging around taking your merry time to get someplace where you're supposed to be, you'll find yourself being relieved of Command in short order.

Tell that to Admiral Frederick Charles Doveton Sturdee. When tasked with intercepting and destroying Admiral Maximilian von Spee's squadron in 1914, Sturdee took his time getting to the Falkland Islands, stopping and inspecting every merchant ship he saw along the way, spending extra days in port at various islands and generally not being in a big hurry. Of course luck was with him as this put him in Port Stanley exactly in time for the attack on that harbour by Spee's group. Had he hurried as he should Sturdee would likely have missed Spee altogether and looked like a fool, which is what his superior First Sea Lord Jacky Fisher apparently hoped would happen. Instead Sturdee became the first British naval hero of the First World War.

I know, "Exception that proves the rule", "If you can't be good be lucky," "Do as I say, not as I do", and all that.
Sorry, couldn't resist. I'm just sayin'

Quote:

Oh, there is one other thing. My wish list includes a fix for the incorrect engine orders and the completely incorrect rudder angles. We hear "Ahead Slow" for the Ahead 2/3 engine order telegraph setting. There is no "Ahead Slow" engine order in the USN...Ahead 1/3 is ahead slow (or slow ahead if you prefer).

I hate that too. I also hate the whole "Yes, Sir!" business. I've been planning for years to make a sound mod for SH4 that would fix all those, conforming to the way it was done in SH1. I've already done a little speech fix for my DBSM translation for OM. I'll try to remember to look into doing as small speech mod that just addresses those two glaring mistakes.

Quote:

The use of 40 degree "standard" rudder is ridiculous, in any Navy. You're putting the rudder into the stops at 40 degrees, which is a good way to jam the rudder hard over. Depending on the design of the ship and the desired performance characteristics, "Standard" rudder is typically 15-20 degrees; "Full" rudder is usually 25-30 degrees and "Hard" rudder is normally 5 degrees less than putting the ram(s) into the stops. Instead of fixing the hydrodynamic drag for a 40 degree "standard" rudder, couldn't we change the normal rudder angle used to 20-25 degrees (and then tweak the turn rate & etc.)?

I hate that as well. Unfortunately I have no idea how to change that.

steinbeck · 05-13-15, 02:48 PM

Quote:

Originally Posted by Sailor Steve

First question: Is it installed to Program Files? If so, make a folder outside of Program Files and move or install it there. That may or may not solve the problem but it's an accepted problem that newer versions of Windows don't like you putting things there.

I run SH3 on Windows 8.1 with no problems at all.

I am not quite sure now, I believe it installs into C:\\Programme Files(x86). I can easliy be moved if that will cure it. I had forgotten the quirky C:\\Drive. I keep my games on my E:\\ Storage drive. which is a big one.

Thank You, I'll look back at an install and see what transpires.

05-12-15, 05:07 PM	#1
steinbeck Frogman Join Date: Mar 2008 Posts: 295 Downloads: 808 Uploads: 0	Re optimum speed Odd that. At one time it was 'ahead standard' the most efficient speed for cruise. I'll try a new start and cruise at 2/3 although with my older set of mods I was fine to get there and back. What is meant by ISP?

05-12-15, 06:48 PM	#2
merc4ulfate DILLIGAF Join Date: Feb 2007 Location: florida Posts: 2,058 Downloads: 210 Uploads: 0	Improved Ship Physics 2.6_TMO_RSRDC_OTC = ISP I normally run the TMO small patch after TMO and before any other mod ... it will avoid the Terrible T issue. __________________ Self-education is, I firmly believe, the only kind of education there is. ~Isaac Asimov~ Mercfulfate 将補日本帝國海軍

05-13-15, 11:36 AM	#4
steinbeck Frogman Join Date: Mar 2008 Posts: 295 Downloads: 808 Uploads: 0	Re optimum speed So I wasn't dreaming,that 'Ahead standard' was the best cruising speed! Anyway, I've adopted the 2/3rds etc and it seems to be ok so far. Amazing how out of touch one gets after a 5 year absence. Jusat wish I coulds get SHIII to work on my Win & rig. Installs from my old disk, even bought a new?? one which turned out to have the same problem. Some Microsoft message, but unable to find any solution. Still got my Grey Wolves mods etc . Very disappointing.

05-13-15, 12:14 PM	#5
Sailor Steve Eternal Patrol Join Date: Nov 2002 Location: High in the mountains of Utah Posts: 50,369 Downloads: 745 Uploads: 249	First question: Is it installed to Program Files? If so, make a folder outside of Program Files and move or install it there. That may or may not solve the problem but it's an accepted problem that newer versions of Windows don't like you putting things there. I run SH3 on Windows 8.1 with no problems at all. __________________ “Never do anything you can't take back.” —Rocky Russo

05-13-15, 02:28 PM	#6
CaptBones The Old Man Join Date: Nov 2010 Location: Rockton, IL Posts: 281 Downloads: 208 Uploads: 0	Real world vs simulation world Not to throw a wrench into the works or dampen anyone's enthusiasm... But, trying to apply real world logic/facts/figures into the simulations we're playing here is not always particularly useful, really. The SH4 game engine, derived from the SH3 engine, simulates a U-boat mechanical/electrical propulsion drive system. It's not even close to the US "Fleet" boats' diesel-electric drive system...not even in the ballpark, totally incorrect. To start with, those boats not only had four diesel-generator sets for main propulsion, but also from one to three auxiliary/emergency diesel-generator sets that could provide all ship's service electrical power, charge the batteries, or drive the propulsion motors just as well as the main DG sets could, but achieving a much slower speed. Yes, the design performance characteristics are useful in attempting to get the simulated submarines to behave as "realistically" as possible. But even there I would suggest the word "accuracy" is more correct than "realism" (which is something that IMHO applies to everything in the world of computer games/simulations...the "realism" involved in sitting at a computer playing games/simulations is 0%). One of the comments made about the meaning of the term "Standard Speed" is quite correct. Ships, warships especially, are designed to meet a broad spectrum of specified performance requirements. Standard Speed is exactly that...a speed (with a specific propeller turn-count) to meet tactical maneuvering requirements, including turn-rate, Advance and Transfer, and Tactical Diameter of turns, in order to be able to safely maneuver in a Formation of other ships, including different Types and Classes. In the USN, prior to WWII as well as now, that speed was 15 kts, at "Full Load" displacement, with excess shaft HP to allow for bottom fouling. Making turns for Standard Speed with a clean bottom and/or at "Light Load" displacement, would typically provide for 16-17 knots or possibly even more, depending on weather and sea-state. For the "Fleet" boats, which were designed to operate with the Fleet, the variable of being able to change the ship's surfaced draft was an added dimension that just serves to make the problem in our game engine(s) even more difficult. Preparing for conducting Full Power Trials and Economy Trials always includes correction of the required turn-count based on draft and bottom condition. USN Economy Trials are always run at 15kts "through the water" (as differentiated from "over the ground"). The propulsion plant is designed to provide for "economical" cruising at that same speed. Here, the key is something that also has been mentioned before in this and other threads on SubSim forums. Standard Speed is the "economical" speed for a warship, but does not necessarily mean the most fuel-efficient speed; it's a combination of time and distance. If you are lolly-gagging around taking your merry time to get someplace where you're supposed to be, you'll find yourself being relieved of Command in short order. Tweaking the game files to achieve 100% "realism" in propulsion plant performance is impossible. It would require a super-computer to do that and that is beyond the financial means of any/all of us...we had one (or two) of those at NAVSEA and used them to make 100% accurate models of ships and ship propulsion plants. Even then, Trials with real ships seldom produced the same results as our simulations. The most powerful computers still can't match Mother Nature's weather and other variables, environmental and man-made. Anyway...not to throw a wrench into the works or dampen anyone's enthusiasm...we do need to use whatever tricks and tweaks that can be done to ensure that our boats can get to their assigned Patrol/Special Mission areas with enough fuel to complete the mission and get back home again. Whether a needed Mod/tweak increases the fuel capacity to ridiculous amounts or ridiculously improves propulsion plant efficiency probably doesn't matter. I would simply finish by suggesting that nobody get too wrapped up in trying to achieve 100% "realism" or accuracy, because it's never going to happen here. Oh, there is one other thing. My wish list includes a fix for the incorrect engine orders and the completely incorrect rudder angles. We hear "Ahead Slow" for the Ahead 2/3 engine order telegraph setting. There is no "Ahead Slow" engine order in the USN...Ahead 1/3 is ahead slow (or slow ahead if you prefer). The use of 40 degree "standard" rudder is ridiculous, in any Navy. You're putting the rudder into the stops at 40 degrees, which is a good way to jam the rudder hard over. Depending on the design of the ship and the desired performance characteristics, "Standard" rudder is typically 15-20 degrees; "Full" rudder is usually 25-30 degrees and "Hard" rudder is normally 5 degrees less than putting the ram(s) into the stops. Instead of fixing the hydrodynamic drag for a 40 degree "standard" rudder, couldn't we change the normal rudder angle used to 20-25 degrees (and then tweak the turn rate & etc.)?