Diesel sub battery issue

[cato13]

Hello,

Im playing the enemy below scenario and have noticed that when my sub is on the surface and running at full speed it drains the battery. why is this so?

also,

why isnt flank speed available in the presets?

[Andrea G]

At full speed the sub uses the diesel engine AND the electric motor to achieve maximum speed that's why it drains the batteries.
It's well explained in the tutorials.

[cato13]

Ive been a self confessed ww2 sub nerd for the best part of 30 years and ive never heard of this.

the battery was only ever used when the sub was submerged. when the sub was surfaced the battery would charge, how quickly it charged was dependent on how many diesel engines were being used for propulsion so the tutorials (which ive done [:)]) are correct in this regard.

the battery would used on the surface only in emergency situations, for example the diesel engines werent working.

The speeds also wrong, should be 20 knots on the surface, not 18.

https://en.wikipedia.org/wiki/Balao-class_submarine

This sounds more like a bug and data error to me.

Sorry if im sounding pedantic about this but i havent played command since it first came out and this sub expansion has peaked my interest again. [:)]

[Primarchx]

As I understand it, SSKs utilize their electric motors for driving the propeller shafts. Those electric motors are fed from the battery bank. The diesel motors are used to charge the battery bank. If an SSK is moving at full speed while snorkeling the diesels are unable to recharge the batteries at the rate those batteries are being discharged to provide that hight speed.

[ultradave]

This is somewhat different than modern SSK subs. Segundo is a WW2 Balao class. The scenario takes place in 1950. It had diesels that drove electric generators that drove the electric drive shaft motors through a reduction gear. At slower speeds, excess electricity is routed to the battery for recharging. At full speed, 100% is directed to propulsion, nothing to the battery. Submerged, electric power from the battery was routed to the electric drive motors.

Now you'd think that that would mean that the battery would slowly drain to provide hotel loads, since all generated power is being used for propulsion (that could be what the game is doing however, the rate seems higher than at slow submerged speed), however there was also a small diesel generator set to supply hotel loads. Based on that, I think that cato13 has a point about draining the battery on the surface at full speed.

However, I did notice one other thing looking at this. Segundo didn't undergo Fleet Snorkel conversion until 1951. In the scenario it's listed with a snorkel and it works.
https://en.wikipedia.org/wiki/USS_Segundo_(SS-398) (halfway down the page in the heading 1945-1953)

[ComDev]

In post-WW2 subs, the diesels are not connected directly to the drive shaft. Rather, the diesels charge the battery that drive the electric motors connected to the drive shaft.

I.e. Diesel-Electric, not Diesel/Electric.

This is how things work in Command also. As such, you can run your battery dry when going flank even with diesels running.

If I remember correctly, a typical SSK can drain the battery in ca 30 minutes at max throttle, but takes 8 hrs to recharge.

[ComDev]

http://www.learning-history.com/world-w ... submarine/

Confirmed:

"As opposed to German submarines at the time which used diesel transmission on the surface and electric transmission subsurface, American diesel-electric engines used on the Gato and Balao Class submarines used diesel engines to charge electric batteries and power an electric motor."

As such it would seem the implementation in Command is correct?

[cato13]

i wasnt aware the US subs in ww2 had a different engine system than the germans.

Very interesting stuff, happy to stand corrected [:)]

How bout not being able to run at flank and the top speed being 18 knots yet that wiki page listing the top speed as 20 knots.

might seem trivial but sure makes a difference making an end around attack. [:)]

[ultradave]

I found a couple places where it listed 20kts and a couple where it listed 18kts as top speed so I guess it depends what they referenced.

[ultradave]

ORIGINAL: ultradave

I found a couple places where it listed 20kts and a couple where it listed 18kts as top speed so I guess it depends what they referenced.

But it seems the bigger item would be as I noted above - at the time of this scenario Segundo had no snorkel. THAT could also make a difference.

[ultradave]

ORIGINAL: emsoy

http://www.learning-history.com/world-w ... submarine/

Confirmed:

"As opposed to German submarines at the time which used diesel transmission on the surface and electric transmission subsurface, American diesel-electric engines used on the Gato and Balao Class submarines used diesel engines to charge electric batteries and power an electric motor."

As such it would seem the implementation in Command is correct?

Not sure. It wouldn't seem that it should drain the battery since even at 100% propulsion power, there was an auxiliary diesel generator to power hotel loads. The only thing would be if it took some battery power to reach 18 or 20 knots, but I couldn't find anywhere that it mentioned something like that.