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Our ship - Shields

Posted: Tue Jul 15, 2008 1:36 pm
by Teaos
Our Ship:

So far we have come to the decision to build a Federation Battleship based in the year 2390; it is of GCS and Sovereign size.

As a battleship it is going to be out fitted with 60cm ablative armour with a high density double hull. This reduced the final production run of the ship by six ships from the original twenty giving us a run of fourteen ships. It also drops its final speed by 12% and agility by 24%.

Now we decide on the shield power and type and energy supply:

You get 3 votes this time. One for the power of the shield, one for the type of shield and one for the power supply.

Since the Pros and Cons are more complicated this time you will have to read bellow to know the cons of each choice.

This will take a bit more thinking that the armour since it revolves around the power supply of the ship.

Firstly here are some examples of current shield strength of other ships. These figures are taken from DITL and are thus not hard canon but for our uses they are good enough.

Sovereign 5.7 million Terra joules
Dominion Battleship 4.64 million TJ
Galaxy 2.7 million TJ
Defiant 2.37 million TJ
D'Deridex 2.3 million TJ
Negh'Var 2.16 million TJ
Scimitar 2.16 million TJ
Akira 1.88 million TJ


Working out the pros and cons of this one were harder than it was for other since the cons don't come in to play until latter.

The Pros and Cons for power:

Pros: Quite obvious. The stronger the shield, the better the protection.

Cons: For every 1 million Terra Joules of energy feed into the shields over the beginning amount of 2 million TJ the size of the power plant of the ship will increase by 4% of its original volume.

Higher energy shielding will also increase the rate at which the emmiters will need to be maintained and refitted due to the highr volume of power they channel.

Example: We decide the shields will be 4 million TJ's. That would increase the size of the power plant 8%. If the power plant was originally taking up 20% of the internal volume of the ship in total, it will now take up almost 22% (20x1.08=21.6). That figure takes into account of everything related to the power plant ie the core its self and all related systems.



Pros and Cons for type:

Pros:
Bubble shields:
Require a lot less maintenance and are less likely to fail during battle. Due to the simplicity of the shielding, given time power can also be redirected from one area of shielding to another during battle essentially recharging the damaged area.

Form fitting shields:
Reduce the surface area of the shields and thus since the same amount of power is feed into them they are more powerful. Depending on the shape and size of the final ship this could very well be over double the strengh per square meter.

It also reduces the apparent size of the ship in total and would thus allow greater maneuverability in close quarter fighting. It also presents a smaller profile to the enemy thus making it slightly harder to hit.

Cons:
Bubble shields:
Cover a larger surface since they have to expand in a bubble over the whole ship. This makes them weaker over all and are thus able to take fewer hits before failing.

Form fitting shields:
Require many more shield emitters and of larger size to be able to hold its shape. They thus require more maintenance and more engineering crew to maintain them.

Due to their complexity it is far more difficult to re direct power and you are thus pretty much stuck with shield damage until the battle is over. Due to the extra effort they need to hold the shield in the conforming shape needed they "waste" upwards of 15% of the power feed into them maintaining this shape.

There could also be a slight issue of "Bleed through" damage when powerful hits strike the shields. A small portion on the strike may break through the shield to the ship bellow even if the shields don't fail out right. This is not an issue on bubble shields due to their distance from the ship.

Pros and Cons of independent power supply:

Pro: By having its own power supply independent of anything else the shields will not fail if the warp core goes off line or other such issues.

Also by not powering up the existing power supply (Probably the warp core) it becomes less fragile as the seem to get twitchy the bigger they get.

Cons: Since it will be a totally new power system it will increase the production time of the ship by one month past the original build time. This is due to the complexity of adding in another power unit.

Since it is a completely new system it will take up more room than just increasing the power out put of the existing power supply.

For every 1 million TJs of power feed into the shields the independent power unit will take up 1% of the internal volume of the ship.

Thus if we wanted a 6TJ shield that would take up around 3.2% extra space by just powering up the existing power supply or 6% if we go independent.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 1:44 pm
by Sionnach Glic
There could also be a slight issue of "Bleed through" damage when powerful hits strike the shields. A small portion on the strike may break through the shield to the ship bellow even if the shields don't fail out right. This is not an issue on bubble shields due to their distance from the ship.
Uh, don't we see that happening quite a bit with bubble shields?

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 1:46 pm
by Teaos
I imagin it would be a lot worse when your shield is 10cm from your hull. I always pictured it as the shield flexing in a bit and thus a form fitting one would suffer more than a bubble one that dozens of meters from the hull.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 2:10 pm
by Graham Kennedy
That's an argument I suggested on the site somewhere or other. If a burn through 200 metres from the hull does damage, the same burn through 5 metres away must surely be more damaging.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 3:22 pm
by Mikey
Agreed. A "bubble" shield can also protect embarking/disembarking craft, etc.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 4:07 pm
by Sionnach Glic
I imagin it would be a lot worse when your shield is 10cm from your hull. I always pictured it as the shield flexing in a bit and thus a form fitting one would suffer more than a bubble one that dozens of meters from the hull.
Oh, I agree completely. Your wording just made it seem like you were suggesting that energy didn't bleed through at all.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 7:12 pm
by Deepcrush
As a battleship it is going to be out fitted with 60cm ablative armour on top of its standard pressure hull. This reduced the final production run of the ship by six ships from the original twenty giving us a run of fourteen ships. It also drops its final speed by 12% and agility by 24%.
Here's a question for you why on earth (which is the most likely place this thing will be built) would you use a Single rate hull? This is a battleship remember? It should have the best hull you can give here. 60cm ablative double hull D/T makes a lot more sense don't you think? What grade SIFs are we going to use? If you're going to give them good on one part then skimp on the others you're still building a battlecruiser, not a true battleship.

On topic,
I voted for the 7m TJ bubble shield because if we're building the king tiger then might as well give it a good hide.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 7:30 pm
by Mikey
Deepcrush wrote:
As a battleship it is going to be out fitted with 60cm ablative armour on top of its standard pressure hull. This reduced the final production run of the ship by six ships from the original twenty giving us a run of fourteen ships. It also drops its final speed by 12% and agility by 24%.
Here's a question for you why on earth (which is the most likely place this thing will be built) would you use a Single rate hull? This is a battleship remember? It should have the best hull you can give here. 60cm ablative double hull D/T makes a lot more sense don't you think? What grade SIFs are we going to use? If you're going to give them good on one part then skimp on the others you're still building a battlecruiser, not a true battleship.

On topic,
I voted for the 7m TJ bubble shield because if we're building the king tiger then might as well give it a good hide.
Nobody ever said that it WOULDN'T have a double hull, Deep.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 7:40 pm
by Deepcrush
But nobody stated that it would either, that's the problem. Its listed as a standard hull with ablative armour, nothing more. So we're already off on the wrong foot as it would seem we are missing something rather important.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 7:42 pm
by Mikey
I don't even think we had a discussion on the hull yet. :confused:

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 7:44 pm
by Sionnach Glic
7 million, bubble, with independant power supply. If we're building a battleship, it makes sense to give it as much protection as possible. These things are going to be expensive to replace.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 7:53 pm
by Deepcrush
Mikey wrote:I don't even think we had a discussion on the hull yet. :confused:
The hull should have been covered under "Armour" as when you have one you also need to work out the other.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 8:28 pm
by Captain Seafort
Rochey wrote:7 million, bubble, with independant power supply. If we're building a battleship, it makes sense to give it as much protection as possible. These things are going to be expensive to replace.
Seconded. It's also important to consider that Teaos' stats describe the bubble shields as being a lot less maintenance-intensive, which is an important point.

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 8:29 pm
by Mikey
Deepcrush wrote:The hull should have been covered under "Armour" as when you have one you also need to work out the other.
OK, we'll do it the easy way:
Is there anybody who honestly believes that we should have anything less than a double D/T hull?

Re: Our ship - Shields

Posted: Tue Jul 15, 2008 8:41 pm
by Deepcrush
Mikey wrote:
Deepcrush wrote:The hull should have been covered under "Armour" as when you have one you also need to work out the other.
OK, we'll do it the easy way:
Is there anybody who honestly believes that we should have anything less than a double D/T hull?
Heavy D/T double hulled you mean right?