Fuel and range issues!

[drakkhen20]

ok so how long did you spend tracking all that? and did you base the ranges off the stock SH4 ranges or off of historical values? and as you stated i take it this is not as easy as just changing numbers?

[Ducimus]

Your asking me specifics for something I haven't put any thought into for a couple of years i'm guessing. off the top of my head, (cause its been too long to remember specifics):

- Actual cruising speed of fleet boats. This was an exrtrapolation based upon reading patrol reports, first hand accounts, and looking at specifics such as how many gallons of fuel oil was actually carried, and doing the math of that against listed statistical range, and how much fuel captains reported as having left over after a patrol. Lots of extrapolation here based on what data I was able to find. One key issue is this: Fleet boats were expected to arrive at their patrol stations by such and such time. They were expected to leave their assigned areas at such and such time. They often traveled to their patrol areas at such a speed as to arrive at their assigned station at their appointed time. At which point, they would cruise at 10 knots or whatever to conserve fuel.

Side note: one problem with online sources is they all plagiarize each other.

- Flat map projection is easy to identify. Go download the google earth application. Then go into SH4, and draw a straight ruler line between two known points. Say, from San Franciso to Tokyo for example. Write the number you get in game down. Then go to google earth app, and do the same again. You'll notice the ingame range is longer. Take the google earth (more like actual) range, multiply it by 0.25 or somewhere there abouts, and add the result to the original range given by google earth. It will come close to the listed range in game.

- Fuel ballast is a bitch. Read around and you'll find two boats of the same class listed at different fuel capacities. Some will be like 94,600 gallons or something like that. Another will be listed at 104,000 gallons or more.

[drakkhen20]

ah, so youve done this already and thats the results is whats in the sim files then?

[Ducimus]

Originally Posted by drakkhen20

ah, so youve done this already and thats the results is whats in the sim files then?

Pretty much. It was the best compromise i could find. For example, in TMO sim file for the gato i think, the @15.19 knots is adjusted to be the exact speed of ahead standard. The way I have the engine throttle set up, ahead standard is 3 engine speed. Look in the submarine cfg file, i think its obvious when you look at the percentages. The 15.19 knots is so exact because i multipied the top speed of the boat by (I think) 75%. (75% being 3/4 or 3 out of 4 engines on the line)


Side note:

The faster you go on the surface, the slower your battery recharge. The slower you go on the surface, the faster your battery recharge. If your going ahead standard you have 3 engines on the line and 1 on the charge.

[drakkhen20]

hhmmm, ok so this is something i dont even need to be messing with then, im sorry didnt mean to seem like i was stepping on your toes there. i think ill just learn how to conserve my fuel better. heres a question though. how many orders do you get before ordered to return to port? is it when all your torps are gone or youve sunk a certain amount of tonnage?

[Ducimus]

The way i intended the fuel, is to travel to your patrol area at standard speed, then kick it down to 2/3rds to conserve fuel. However, this also involves budgeting/managing your fuel. Everyone likes to kick to 2/3ds (9-10 knots or there abouts) and not worry about it. I've always felt like this is the antithesis to a simulation. It's also what people are used to in SH3 and uboats.

Easiest way i find to manage fuel is:
- at the start of a patrol, go to standard, and ask for max range at current speed.
- plot a 1 way route to your patrol area. Take that range, multiply it by 2. Thats your round trip fuel consumption.
- Take that round trip number, and subtract it to your first number of max range at current speed. The remainder will be how much fuel you have to patrol with at standard. It will be a small number, however this number will be stretched greatly by crusing at 2/3rds while in the patrol area. Seriously.

I did just that when i tested this concept. I took that remainder patrol number after doing exactly what i just described, and in a test modlet, imputed that range at 15.19 knots. Then cruised at 2/3rds. to see if the range was adequate, which it was.

Try it.


As for patrol orders. How many missions you can get depends on what missions are nearby, how much fuel and torpedos you have. Reallsitically, you can do as many as you want thats available, or none at all. All that really counts in the end is how much renown you earn.

[drakkhen20]

alright ducimus, will do. thanks for the replies. ill try my best.



regards,
drakkhen20

[drakkhen20]

ok so even if you have standing orders you can sail to your home port and still end the mission and dock ? because i know in stock SH4 you cant.

[Bilge_Rat]

Ducimus is correct.

I had also looked into changing the fuel usage since I thought TMO 2.5 was too generous, but you can't really use the RL range since:

-fuel usage of subs in game is off, it uses too little fuel at ahead 2/3rds and too much at ahead standard;

-the SH4 flat world distorts the real world and distances in SH4 can be up to 25% longer than in RL.

I did change my TMO instal, basically took the RFB 2.0 figures and increased them by about 25%, so you still have to worry about fuel usage more than in TMO 2.5.

If you use RFB 2.0, there is a mistake in the files for many of the subs. the read me to RFB 2.0 states the range that each sub class should have, but if you check the files, you will see that the actual range is less than that, by a factor of 10-20%, which when coupled with the flat world issue means you are really shortchanged in fuel.

[drakkhen20]

yes, excellent resposes. thats why i asked ducimus before i dug into it. seems theres more to it then just going in and editing a few numbers here and there. but i've gotten better at saving my fuel and measuring it constantly which i suppose is what they did back then also; so it adds more to the "imersion effect" for me. since this is a reaccuring issue in the game there should be a more indepth strategy for using and consuming fuel during a patrol written up and sticked or in a readme. thanks again guys i can finally fully play SH4 Fleetboat style now and not be so frustrated with running out of fuel all the time.



regards,
drakkhen20

[Beardmoresam]

Hi, this thread caught my interest and seeing that some very knowledgeable people are answering, I have a question that has caught my interest a while back. I'm hoping some of you might know the answer.

If Standard speed is running the three main diesels or generators, and full is the 3 main diesels and the Auxiliary Diesel, is flank just squeezing more turns out of the engine? or is it drawing on the batteries (as they would have done in RL) to assist the diesels in getting those emergency extra turns?

Running TMO 2.5 btw.

Thanks, Sam.

[TorpX]

Standard is using 3 main diesels, full is using 4 diesels, flank is using 4 diesels and current from the battery. This is not accurately modeled in the game, though.

[drakkhen20]

well you know theres alot of other things as far as propulsion that are lacking. like the fact that you cant individually adjust the speed of the port or starbaord! you just have to se each at the same speed. so this makes it harder to manouver the sub everywhere.

[Gilead Abyss]

Hello all,

I've been reading the TMO thread, most recently the posts by Ducimus about reworking the cruise speed/range/battery recharge in 2.0. It prompted an idea, and I just ran a search to see if this is discussed elsewhere.

I need to test this again, but I think with some experimentation it is possible to approximate a great circle route (for example from Midway to Luzon/Tokyo/anywhere by laying several waypoints. 4? 10? Have to try it out.

The reported range to course end comes back as fewer nm even though on the flat map projection in game on screen it looks longer.

Is anyone already doing this routinely? Does it save enough fuel to be worthwhile? I like the idea of it for simulation value, but I can imagine getting tired of plotting a dozen waypoints every time I want to sail from A to B.

Obviously this only really makes sense for long transits, not cruising the Celebes.

Any thoughts from SH4 veterans?

Thanks all

[TorpX]

If you can get a great circle route in the game to work, please post the particulars so we can confirm this.

I rather doubt this will work out the way you suggested, but if I happen to be wrong, this would make for a more interesting game.

AFAIK, none travel in this game using a great circle route. I certainly would if there was any advantage in it, though. I wouldn't say it is too tiring. I don't use high TC, and one only needs to make very long transits twice per patrol. Anyway, this was done in real life, so why should we consider it too difficult for us?

The "flat-earth" SH4 world has always bothered me.