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View Full Version : Fuel and range question -Pearl to Borneo area


jamz
08-26-08, 12:32 PM
In a Gato class boat, is there enough fuel/range to make it from pearl to the south china seas, and come back, maybe with a stop to top off at midway? I'm noticing that even cruising at 10 kts exactly, not using the battery, but stopping to submerge, I don't have the gas to make it even halfway back.

I'm tending to go all the way to Brisbane, then up to the Borneo area to patrol, then back to brisbane then to pearl. What gives? I should have 10k miles, right? All this commuting is tending to be a serious drag.

The time in summer '42, and there are no US bases other than 2 in Australia, midway and pearl. How do you guys play this out when you have to go this distance?

SteamWake
08-26-08, 12:40 PM
You should have enough fuel...

In the 'stock' game run at around 9.5 knots while surfaced for best range instead of ahead standard.

You can do this by clicking the tab beneath the telegraph it will change from notches to actual speeds.

Even an hour or two at flank is dicey so plan your attacks well ahead of time.

The 'extending range by running submerged on batteries' has been the subject of much debate. In real life it would not be possible due to the energy spent recharing the batterys. However I personally feel it does extend range. As a standard operating procedure my boats tend to spend a lot of their time submerged in the daylight hours.

One more tip, if you get a 'patrol area' mission just sail to the area and cut the engines and drift around for the patrol duration, diving when aircraft are spotted and only using engines when prosecuting a contact.

Fincuan
08-26-08, 12:42 PM
Y
The 'extending range by running submerged on batteries' has been the subject of much debate. In real life it would not be possible due to the energy spent recharing the batterys. However I personally feel it does extend range.

Trust me, it doesn't work. Might work in rough weather, but definitely not under normal conditions.

jamz
08-26-08, 12:48 PM
I've had to basically replay maybe 4 patrols due to not being able to get back, it's most frustrating. I recall in SH3 how you could seriously extend your range with 1/3 propulsion underwater, surfacing only to recharge the batteries. Maybe I'll try that as a test.

SteamWake
08-26-08, 01:19 PM
Y
The 'extending range by running submerged on batteries' has been the subject of much debate. In real life it would not be possible due to the energy spent recharing the batterys. However I personally feel it does extend range.

Trust me, it doesn't work. Might work in rough weather, but definitely not under normal conditions.

Like I said its been a subject of debate for a long time. I must admit that my 'evidence' is purely anecdotal.

jamz
08-26-08, 01:51 PM
Well, I did a little test, probably has been done before, but I like to pee on the electric fence myself sometimes.

I drove from Pearl to Dutch Harbor, around a 2100 NM trip, hoping to meet Captain Sig Hansen on the Northwestern. Went three times, once on batteries alone, only surfacing long enough to re-charge them, once at 1/3, and once at 10 kts, supposed best range speed.

The results:

Batteries: 68 fuel units remaining. Burned 32 Units.
1/3 propulsion: 84 Units remaining, burned 16 units.
10 kts: 86 units remaining, burned 14 units.

So yeah, recharging the batteries is pretty inefficient. I'd still like to know why I never can make it back to pearl though, I like to think I'm pretty stingy about fuel use. :/

Quillan
08-26-08, 03:16 PM
When running out of Pearl Harbor, my typical patrol starts with a speed run to Midway where I top off with fuel. From there, I head off to where I need to go, which is typically in the area of Japan or Formosa. I have no problems with fuel barring damage. I usually arrive with 80-85% fuel remaining, and head back when I get to about 50%. Stay at 9-10 knots in the Gato+ boats and that should work. The only times I've had problems is when I suffered battery damage, and the automatic recharging didn't switch off. That seriously upped the fuel consumption, to the point that I ran out of fuel about 1500 nm east of Tokyo.

SteamWake
08-26-08, 03:41 PM
[quote=Quillan]The only times I've had problems is when I suffered battery damage, and the automatic recharging didn't switch off. [quote]

Yes watch for this too it will catch you off guard.

and the stop at midway is more or less manditory :rock:

Bosje
08-26-08, 05:24 PM
my 2 cents:

not to bore you with SH3 but I remember reading that they increased ranges in the GWX supermod because the game does feature the authentic ranges but it doesnt take the shape of the earth into account

i'm not exactly sure how it works but it appears that the shortest distance between, say, pearl harbor and tokio is NOT a straight line drawn on some 2 dimensional map

the trip is taken across a sphere so in fact, taking a kind of long curve, covers a significantly smaller distance than the one you get when you draw a line on the map

so... historically the boats would be able to make the trips we are all assigned, but in the game you are forced to cover a lot more, ehm, water on the same mission

that's why in GWX 2.1 you get more fuel in your sub, which creates actual historical range

I too have had to refuel in darwin and then go all the way up again to Luzon to make it there with fuel to spare. results in a patrol lasting 3 months with maybe 3 interesting days where you get contacts etc. I love that feeling, dont get me wrong, but perhaps the modding community could look into this

edit: ps i currently start my missions by going to 10 knots and checking the range with the navigator, drawing some lines and doing some math. then i decide if i am going to make it. if i cant, i just stop by midway first thing, or take a long detour visiting the aussies, that helps with the current setup

jamz
08-26-08, 05:27 PM
The only times I've had problems is when I suffered battery damage, and the automatic recharging didn't switch off. That seriously upped the fuel consumption, to the point that I ran out of fuel about 1500 nm east of Tokyo.

Ahh, very good point. I'll be on the lookout for this. Going to install TMO tonight I think, start patrol 5 for like the seventh time ;) and give it a whack and make sure my batteries stay okay. :)

SteamWake
08-26-08, 08:28 PM
Wow damn good thing I participated in this thread. I almost got nailed by this tonight !

I was on patrol just of mainland japan... plenty of fuel left to get home when I was done.

We fullfilled the mission orders and turned for Midway. Running at standard (10 knots... RFB) something wasent adding up. I checked the range and sure enough we werent going to make it at present speed. Battery gauge 'looked' full so I checked the orders... sure enough we were still tryin to charge the batts. I checked the batts and they were at 98%.... they could not be filled to 100% no matter how long I ran.

You see I recieved a few 'complaints' from some shore batteries... yea dumb I know and one of the damaged systems was the batterys. So... even though the repair crew did a yeomans job evidently they couldent get the batts back to 100%.

So... lesson learned. Watch for this little snafu it could leave you bobbing around unable to complete and having to start over :yep: