TWO KNOTS AT FLANK SPEED?

[VONHARRIS]

Originally Posted by Mag

I'm on the surface at ahead full. To conserve fuel is dive to PD. My speed decreases from about 17 knots to 2 @ flank speed! If this is normal as the battery is drained, I haven't noticed this before.

What's wrong?

Does it happen during every patrol you run?

Do you recharge your batteries while on the surface?

Are using SH3 Commander , and if yes do you have the mulfuction and sabotage option checked?

I avoid prolonged runs on anything higher than "ahead standard" for durability reasons. Although I never had any problems with engines in SH3, in SH2 I run into problems with engines if pushing them in "ahead full" or "ahead flank" for long stretches - "engines are overheating!" and if I neglect it - "engines damaged!" - which will then take some (more realistic) 3 or more hours to fix with the boat stoped.

This has been added to SH3 with the exellent H.sie's V16B1 realism pack and Stiebler's add ons.

[BigWalleye]

Running on batteries won't conserve fuel. R/L, it takes more energy to charge the batteries than you can get out of them, usually about 15-25% more. (This is the myth of the electric car.) I doubt the devs actually modeled this, but it's built into ranges and speeds. You use just as much fuel going slow on one engine while the other recharges the batteries as you do going much faster on two engines at normal propulsion. And you go slower still on batteries. So the distance traveled on a "tank of gas" decreases the more you use the batteries.

All WW2 submarines were spec'ed to deliver optimum cruise radius at 10 knots. So that's what the builders delivered. Set you speed to 10 kts and you will see greatly improved range. That's what the R/L sub skippers did, and it works in the game. Also, check with the Nav officer on range remaining. It'll quickly show you optimum cruising speed.

[Sailor Steve]

Originally Posted by BigWalleye

Running on batteries won't conserve fuel. R/L, it takes more energy to charge the batteries than you can get out of them, usually about 15-25% more. (This is the myth of the electric car.) I doubt the devs actually modeled this, but it's built into ranges and speeds. You use just as much fuel going slow on one engine while the other recharges the batteries as you do going much faster on two engines at normal propulsion. And you go slower still on batteries. So the distance traveled on a "tank of gas" decreases the more you use the batteries.

True in real life, and true in SH4. Not true in SH3. Battery charging in the game doesn't work properly, and does indeed give you an advantage, or so many reported in the early days. I've never tried it myself, since it's unrealistic even if it does work.

[MantiBrutalis]

Originally Posted by Sailor Steve

True in real life, and true in SH4. Not true in SH3. Battery charging in the game doesn't work properly, and does indeed give you an advantage, or so many reported in the early days. I've never tried it myself, since it's unrealistic even if it does work.

Charging batteries in SH3 does not consume fuel. Doesn't really make a difference, if not abused.

[Jimbuna]

Originally Posted by MantiBrutalis

Charging batteries in SH3 does not consume fuel. Doesn't really make a difference, if not abused.

Imagine the scene...you surface and drift because your out of fuel but suddenly as if by magic, your batteries are charged up.

To each their own I suppose but I certainly don't subscribe to that.

If you run out of fuel simply press the Esc key (if you must) and hyper drive back to base.

[VONHARRIS]

Originally Posted by Jimbuna

Imagine the scene...you surface and drift because your out of fuel but suddenly as if by magic, your batteries are charged up.

To each their own I suppose but I certainly don't subscribe to that.

If you run out of fuel simply press the Esc key (if you must) and hyper drive back to base.

For me in that occasion : Scuttle the U-boot and surrender to the Allied Forces , if you are lucky enough.

[aj906]

Originally Posted by VONHARRIS

For me in that occasion : Scuttle the U-boot and surrender to the Allied Forces , if you are lucky enough.

Depending upon where I am I use the escape option because you could have got aide from either other boats (increasingly unlikely) but also Bv 138s (again, increasngly unlikely) which also used diesel, albeit this option is rather dubious.

Obviously I use the trusty old dice method for calculating:
1940 - 1941: if I role 2 - 5 I 'escape'
1942: if I role an even number I 'escape'
1943: I role twice and if the product is 18 or better then I 'escape'
1944: I role twice and if the product is 25 or better then I 'escape'

I also add the extra distinction for dates:
Nord Atlantik I use 10.1940 - 1.1945
Atlantik and Süd Atlantik I use 10.1940 - end of Mai 1944

The distinction is that at least the Bv 138s of Luftflotte 5 still were operate from Norway (although I have to get within 950 kilometres of major bases like Bergen, Trondheim or Narvik for this to be of any help). I know it is a rather feint hope and perhaps ahistorical, but then SH3 doesn't really give the option of refueling at sea beyond the stock milk cow option..

I'm no mathamatician so I don't know if any one year - aside from 1941 - stands a better chance of surviving running out of fuel or not. But as a general rule I always turn for home - regardless of torpedo situation when I judge my reserves to be about 45%, taking the most direct route there. If I'm in the Süd Atlantik and based in Norway, then I usually just forgo the bonus points and drop that to 40% and then aim for somewhere like St Nazaire.

[BigWalleye]

Originally Posted by Sailor Steve

True in real life, and true in SH4. Not true in SH3. Battery charging in the game doesn't work properly, and does indeed give you an advantage, or so many reported in the early days. I've never tried it myself, since it's unrealistic even if it does work.

You are saying, Steve, that fuel consumption in SH3 is based on speed through the water and not on engine settings? So you can run at Flank speed in a heavy sea and use less fuel than at Standard in calm weather? That is so counterintuitive and so wrong that it ought to be a priority item for fixing. I hope someone is working on it! (Stiebler, can you help? I'm guessing it would require a code patch.)

[Mittelwaechter]

Do you remember the scene in Das Boot, when Kriechbaum mentiones in the heavy storm "we don't make any speed/progress over ground" and the Kaleun orders to dive? Running on batteries did save fuel under certain circumstances, because they where able to move at all. It happened in real life too.

[BigWalleye]

Originally Posted by Mittelwaechter

Do you remember the scene in Das Boot, when Kriechbaum mentiones in the heavy storm "we don't make any speed/progress over ground" and the Kaleun orders to dive? Running on batteries did save fuel under certain circumstances, because they where able to move at all. It happened in real life too.

May I suggest you read Dick O'Kane and Ned Beach, two American submarine skippers of WW2. Both describe running submerged in storms. Not to mske more progress, but to reduce the wear and tear on the boat and, equally important, on the crew. IIRC, O'Kane nearly had a lookout killed by being battered by a huge wave. The notion that somehow a WW2 submarine could actually make better speed submerged than on the surface is not borne out by the historical record. Even a u-boat could make 4-5 knots in bad weather on the surface, and could not sustain that speed submerged for more than an hour or so. Storms at sea often last for days.

[Sailor Steve]

Originally Posted by BigWalleye

You are saying, Steve, that fuel consumption in SH3 is based on speed through the water and not on engine settings? So you can run at Flank speed in a heavy sea and use less fuel than at Standard in calm weather?

No. I'm only saying that running underwater then surfacing to recharge your batteries will actually extend your range in the game. The energy is not lost as it should be when recharging. Yes, this is totally unrealistic, and it was fixed for SH4.

[Jimbuna]

Originally Posted by VONHARRIS

Are using SH3 Commander , and if yes do you have the mulfuction and sabotage option checked?

That was my thought

[Mag]

Originally Posted by VONHARRIS

Does it happen during every patrol you run?

Do you recharge your batteries while on the surface?

Are using SH3 Commander , and if yes do you have the mulfuction and sabotage option checked?

This has been added to SH3 with the exellent H.sie's V16B1 realism pack and Stiebler's add ons.

Does it happen during every patrol you run?
- Yes, it happens every patrol, but it does make sense that the engines would decrease in speed as the battery is drained.

Do you recharge your batteries while on the surface?
- yes, i recharge batteries on the surface.This is automatic.

Are using SH3 Commander , and if yes do you have the mulfuction and sabotage option checked?
- no, I'm not using SH3 Commander.

To answer a previous post, I don't leave port submerged. I would leave port surfaced, running at ahead full. I know that not wise, but wanted to get to patrol area asap.

I'm getting mixed opinions about fuel conservation. I mean if running submerged does not conserve fuel, how can you arrive at a patrol area that is over 3500KMs away without running out of fuel?

[VONHARRIS]

Originally Posted by Mag

how can you arrive at a patrol area that is over 3500KMs away without running out of fuel?

Easy , you travel on the surface at ahead one third. With calm weather , this gives you about 8 - 9 kts speed which is satisfactory cruising speed.
It takes more time but it saves fuel and lets you return to port safely(fuel-wise)

Use ahead full of flank for interceptions only.

[Pisces]

Try your (nautical) mileage when speed is set to different levels. (and given time to achieve it) You'll see.