Secondary shield on Atlantis?

[mikeroq]

I was just thinking about this the other night, why don't ships and the such have 2 shields.

Wouldn't the second shield help reinforce the first one while its under fire? When the first shield fails, the second one will provide more shield time, extending a battle.

[FreakyMcD]

I was just thinking about this the other night, why don't ships and the such have 2 shields.

Wouldn't the second shield help reinforce the first one while its under fire? When the first shield fails, the second one will provide more shield time, extending a battle.

Every vessel in the Stargate universe that uses shields (apart from Atlantis) would need some sort of capacitor to store large amounts of energy since the ships power core will have a limit on how much power it can generate per second. If a ship is going to have a completely separate seconday shield it will need more shield emitters and capacitors in order to function properly. So the ship might as well use any energy that would be used for a second shield to power the primary shield.

Atlantis is powered by ZPM's so it presumably doesn't have any way to store energy for it's shields since ZPM's provide so much. If Atlantis did have capacitors to store energy then the team could hook up naquahah generators and possibly connect the city to the Deadalus's power grid in order to store energy to power the shield when needed.

But since some much of the hull of Atlantis has windows, open walkways and very thin doors it would be stupid not to have all these areas covered by independant forcefield/shields so large portions of the city don't become a vacuum if the shield falls. But this is the Ancients we're talking about here, we haven't seen them do a lot of smart things.

[ussrelativity]

Kind of like the Scimitar from Star Trek: Nemesis? Which had primary and secondary shields (according to Mr. Worf).

http://img86.imageshack.us/img86/2165/scimitarhk2.jpg

She's a predator, you know!

It sure was pretty awesome! I wish that more elements in sci-fi had more than one shield.

[Gravity]

We all know that the Ancient are one of the oldest space faring races out there…

Don’t tell me they never had a hull breach or shield failing on them! I am sure that it happened quite a couple of times and that they have some safety procedures in place, even in the current situation we find ourselves in…

I mean Atlantis is the Nexus of all things Ancient… would they really risk their UBER city to go out like this? I doubt it… If they can create a race like the Asurans, they surely have the knowledge to protect their City in a time like this!

[Anubis-]

I'm allways wondering, why Ancient does not make so, that shield got power, which is fired on it. Like undending, Carter take power from Ori blast.

If Atlantis shields take power from energy blast, there was no worry about ZPM:s.

And I did not mean, that is only powersource, I mean that shield are, yes powered by ZPM, but collects energy, which is hidden trought it to some kind batterys.

[SaberBlade]

Using enemy weapon fire would be a bad idea.

Some Unending Spoilers

Spoiler:

Yes Carter used it as a power source, but the Odyssey still blew up as it needed direct contact with the beam. If Atlantis took a direct hit, it would still be badly damaged because the city is supposed to be fairly fragile (as stated by McKay) so even using lightning was a risky plan.

The Ancients wouldn't need to use anything like that anyway, because they always expected to be there and to have three ZPM's being used at all times. You can't expect them to have a plan in place for that when they expect their shields to hold

[Professor Chaos]

It would be smart to install an

Spoiler:

Asgard

power core that they got in

Spoiler:

unending

just to add more juice to the existing zpm's.

[J_B]

If that was the primary shield the rooms wouldnt of flooded 1 by 1 it would of gone alltogether....the entire city was covert in water you can see this when the english guy shows wier that another room was flooded

Actually it was the main shield. It was specifically said by McKay that because of the low power levels, it started sacrificing less needed parts of the city in order for it to be able to preserve more important parts.

McKAY: The forcefield holding back the ocean has collapsed to its minimum sustainable levels. Look, you can see: (he turns to a screen showing the star shape of Atlantis and indicates a couple of points on it) here, and here, where the shield's already failed and the city's flooded. It could have happened years ago. This section is likely more protected because of the Stargate.

SHEPPARD: What if it fails completely?

McKAY: It's a matter of when, not if.

Hence that's why water got in, because the main shield went down in those areas of the city, not because it had any sort of a backup shield or anything like that. Not only that but if it didn't have power to work the main shield covering the city, then how on Earth could it have the juice to power a backup shield?

As TA said, the entire city was covered with water, the shield had collapsed to minimum sustainable levels according to McKay. I believe that the main shield had collapsed completly, and only emergency forcefields that protected the open windows and spaces were keeping the city dry. The english guy pointed out another part of the forcefield collapsing, which was shown as a bright flash and bubbles rising in the affected area. The city was sacrificing parts of itself to maintain power to the forcefields in the central tower. Then as they were about to collapse completly, the failsafe kicked in and the city broke the surface just as the shield collapsed. You saw water running off the city as it broke the surface, and as it settled, you saw water running off the glass.

Again I direct you to:

McKAY: The forcefield holding back the ocean has collapsed to its minimum sustainable levels. Look, you can see: (he turns to a screen showing the star shape of Atlantis and indicates a couple of points on it) here, and here, where the shield's already failed and the city's flooded. It could have happened years ago. This section is likely more protected because of the Stargate.

SHEPPARD: What if it fails completely?

McKAY: It's a matter of when, not if.

Hence it didn't fail completely, or use any sort of backup shields or forcefields. It was the main shield that started sacrificing less important areas to be able to continue to have enough power to protect the more important parts of the city!

[J_B]

I'm allways wondering, why Ancient does not make so, that shield got power, which is fired on it. Like undending, Carter take power from Ori blast.

If Atlantis shields take power from energy blast, there was no worry about ZPM:s.

And I did not mean, that is only powersource, I mean that shield are, yes powered by ZPM, but collects energy, which is hidden trought it to some kind batterys.

No doubt the Lanteans were smart enough to be able to figure out a way for Wraith weapons impacts to power it. However had they done that, then Atlantis would have always been safe, therefore no real drama or problems anytime the Wraith attacked. ZPM's provide the power, however are rare, so that means they have to be more careful.

I think it would turn a lot of people off watching if everytime a Wraith fleet showed up & Shep & Co are laying about on sun loungers on one of the outside balconies watching the pretty colours of the Wraith weapons impacts on the shield. They'd always be safe as there would never be any problems of them running out of power, so there would be no drama. Realistically, they were smart enough to do so, & probably would have at least attempted it in real life, but for tv land, it would't be a good thing to have had them do.

[RogueEntity]

Actually it was the main shield. It was specifically said by McKay that because of the low power levels, it started sacrificing less needed parts of the city in order for it to be able to preserve more important parts.

Hence that's why water got in, because the main shield went down in those areas of the city, not because it had any sort of a backup shield or anything like that. Not only that but if it didn't have power to work the main shield covering the city, then how on Earth could it have the juice to power a backup shield?

Hence it didn't fail completely, or use any sort of backup shields or forcefields. It was the main shield that started sacrificing less important areas to be able to continue to have enough power to protect the more important parts of the city!

I disagree.

Spoiler:

In First Strike, when they sunk the city again, the whole shield was active, and it was the normal dome shape.

The main shield is a large dome shape when powered, they didnt have the power with the naquadah generators to maintain the shield when they were under water, though they connected them anyway, when the power begain to fail completly, the city rose to the surface, and it failed completly by the time they came to a rest. McKay stated in that episode that they didnt have the power to operate the shield, even without the weight of the ocean pressing on it. So from that I infer that:
a) the shield, even at minimum levels requires too much power for the Naquadah generators to operate, or
b) the shield at minimum levels wont protect the city from direct attacks since it only protects the open areas. And thus, if the shield was dropped to minimum levels, the asuran energy beam would have destroyed atlantis.
I mean, if they could safely drop to minimum levels, skin tight, and covering the whole of the city, that is how the ancients would have done it, and also what McKay would have done when the wraith were laying siege to the city to extend the power available. Just because ZPMs produce incredible yet finite quantities of power is no reason to be inefficient.

Since the shield had collapsed, to its minimum levels, i.e. the main dome had failed and only the section-specific forcefields (which I imagine are part of the main shield anyway) were operating, holding back the water, the rest of the open areas were long since flooded, yet the city was dry, with sections of the shield collapsing in empty areas to maintain power to the shields protecting the central tower.

Thus, Atlantis does indeed have "secondary shields" in the form of forcefields protecting the open areas when insufficient power is available to maintain the dome shield which having a larger surface area would require many times more power. It is very possible that the main shield just falls back to this minimum level since the city was designed to fly through space, that if power was required for something else, say to increase the hyperdrive speed, the shield power could be reduced to these minimum levels without compromising the athmosphere.

Just my 2¢

[J_B]

I disagree.

Spoiler:

In First Strike, when they sunk the city again, the whole shield was active, and it was the normal dome shape.

The main shield is a large dome shape when powered, they didnt have the power with the naquadah generators to maintain the shield when they were under water, though they connected them anyway, when the power begain to fail completly, the city rose to the surface, and it failed completly by the time they came to a rest. McKay stated in that episode that they didnt have the power to operate the shield, even without the weight of the ocean pressing on it. So from that I infer that:
a) the shield, even at minimum levels requires too much power for the Naquadah generators to operate, or
b) the shield at minimum levels wont protect the city from direct attacks since it only protects the open areas. And thus, if the shield was dropped to minimum levels, the asuran energy beam would have destroyed atlantis.
I mean, if they could safely drop to minimum levels, skin tight, and covering the whole of the city, that is how the ancients would have done it, and also what McKay would have done when the wraith were laying siege to the city to extend the power available. Just because ZPMs produce incredible yet finite quantities of power is no reason to be inefficient.

Since the shield had collapsed, to its minimum levels, i.e. the main dome had failed and only the section-specific forcefields (which I imagine are part of the main shield anyway) were operating, holding back the water, the rest of the open areas were long since flooded, yet the city was dry, with sections of the shield collapsing in empty areas to maintain power to the shields protecting the central tower.

Thus, Atlantis does indeed have "secondary shields" in the form of forcefields protecting the open areas when insufficient power is available to maintain the dome shield which having a larger surface area would require many times more power. It is very possible that the main shield just falls back to this minimum level since the city was designed to fly through space, that if power was required for something else, say to increase the hyperdrive speed, the shield power could be reduced to these minimum levels without compromising the athmosphere.

Just my 2¢

Jebus Christ, what is it with some people around here!

In First Strike when they had the shield up, they still had a ton of ZPM power left. Therefore there was enough power still left for the shield to cover the entire city. If you disagree, then watch how they are able to take off using the Star Drive, as well as activate the shields & jump into HS. Couldn't do that without power!

Again I refer you to:

McKAY: The forcefield holding back the ocean has collapsed to its minimum sustainable levels. Look, you can see: (he turns to a screen showing the star shape of Atlantis and indicates a couple of points on it) here, and here, where the shield's already failed and the city's flooded. It could have happened years ago. This section is likely more protected because of the Stargate.

SHEPPARD: What if it fails completely?

McKAY: It's a matter of when, not if.

To it's minimum sustainable levels. It DID NOT collapse completely, it simply started shrinking itself in size to reduce strain on the ZPM. It sacrificed non critical areas to flooding so that main sections of the city could still be protected from the shield.

All areas that were not flooded were still protected by the shield (The main shield, the only 1 it has).

Then there is this:

WEIR: The shield has held back the ocean for centuries.

McKAY: And probably would have kept going for years more, but our arrival changed that. Now it's nothing more than a thin shell between the buildings and the water.

WEIR: We stopped exploring.

McKAY: The damage was already down. Another section of the city on the far side was flooded an hour or so ago.

GRODIN: Even occupying this room is draining power.

McKAY: We need to evacuate the moment Colonel Sumner reports back it's safe.

WEIR: You're saying we have to abandon the city?

(A brief rumbling comes from nearby.)

McKAY: The sooner we leave, the longer that shield holds.

or this:

WEIR: How are we doing? Look, if we can just buy ourselves another day, maybe we could ...

McKAY: This city is sacrificing parts of itself in order to maintain these main areas but catastrophic failure is inevitable.

or this:

WEIR: Major Sheppard, the shield is about to fail and the ocean is about to come crashing in on us. Do you have a better place for us to go?

(On a computer screen, the message “SHIELD FAILURE IMMINENT” appears.)

McKAY: The shield is collapsing!

(There's a flash of light as the shield begins to fail and the base jolts so hard that everyone is thrown off their feet. From an external viewpoint, the city of Atlantis begins to rise off the ocean floor. Inside, people scramble to get out of the way as the base continues to shake, causing boxes and crates to fall and crash around.)

As to your observations. Obviously the Naquadah genrators can't power any part of the shield no matter how small an area they want to cover because McKay says it in the episode.

"McKAY: We're working on that, but even with our most advanced naqahdah power generators, the equations are coming up far short."

They couldn't even power the deep space sensors or anything like that!

As for the bit about minimum levels, again your stating the obvious that really has nothing to do with the discussion. The shield only goes down to minimum levels when there isn't enough power to maintain the forcefield around the entire city. Therefore what does it take to be able to withstand enormos impacts on the shield.....You guessed it.....Energy!

Therefore the fact that it wouldn't have stood up to Wraith or Asuran attacks when working at minimum is kind the most obvious thing I've heard in a long while!

Lastly the areas that came up-unflooded were protected by the shield. The parts that were flooded were the sections that the main shield sacrificed.

Think of it a little like what happened in 'Revisions'. The dome had power issues, so it started sacrificing areas of the city to lessen the power drain. Meaning it could provide power for longer without toally failing. Only difference was that the dome wasn't under water.

So all this talk of secondary shields & the like is totally unfounded speculation on the fans part. There has never been any indication that it has any.

If it had backup shields, then why didn't they raise in 'The Return' after the Asurans knocked out the main shield.

Why didn't sections start bringing up forcefields to locked areas when the city put itself into lockdown in 'The Hot Zone'.

In 'The Long Goodbye' when Weir locked the city down completely, how come no force fields were raised like in 'Submersion' that prevented everyone from getting around the city.

So until secondary shields or internal forcefields or whatever are shown, then you may have cause to beleive it. However right now it's totally unfounded!

[happyclappy]

instead of a second shield i think it has areas where it is 'space tight' for example where the secondary controll room is.... maybe incase the shiled fails... close air tight doors and live in the interior. would make sence....

[RogueEntity]

When I said Secondary shields, I was referring to minimum shielding that protects the city's open space when their isnt enough power to operate the main shield to protect the entire city as usual. Therefore, if the power levels fall too low, the dome will eventually shut off, leaving minimum shielding protecting the vital areas only, these will be able to stay operational for a lot longer, but they would not protect the city as the main shield would.

In First Strike when they had the shield up, they still had a ton of ZPM power left. Therefore there was enough power still left for the shield to cover the entire city. If you disagree, then watch how they are able to take off using the Star Drive, as well as activate the shields & jump into HS. Couldn't do that without power!

To it's minimum sustainable levels. It DID NOT collapse completely, it simply started shrinking itself in size to reduce strain on the ZPM. It sacrificed non critical areas to flooding so that main sections of the city could still be protected from the shield.

All areas that were not flooded were still protected by the shield (The main shield, the only 1 it has).

Therefore the fact that it wouldn't have stood up to Wraith or Asuran attacks when working at minimum is kind the most obvious thing I've heard in a long while!

Lastly the areas that came up-unflooded were protected by the shield. The parts that were flooded were the sections that the main shield sacrificed.

Think of it a little like what happened in 'Revisions'. The dome had power issues, so it started sacrificing areas of the city to lessen the power drain. Meaning it could provide power for longer without toally failing. Only difference was that the dome wasn't under water.

Why didn't sections start bringing up forcefields to locked areas when the city put itself into lockdown in 'The Hot Zone'.

In 'The Long Goodbye' when Weir locked the city down completely, how come no force fields were raised like in 'Submersion' that prevented everyone from getting around the city.

So until secondary shields or internal forcefields or whatever are shown, then you may have cause to beleive it. However right now it's totally unfounded!

In Rising Pt2, Rodney says the forcfield holding back the ocean collapsed to minimim sustainable levels, Grodin also pointed out where one of these had collapsed, giving off a flash of light as it did. In that shot, you can see the city is in direct contact with the ocean, the forcefields are protecting the open windows. Later in the ep, when the city is rising, you can see the water running off the glass as it is rising, now you could argue the shield had failed and the water was only now in contact with the city, but if this was the case, we would see the shield in operation from every external view of the city used in the ep, as the shield has always been visible with a yellow glow in later eps.

So, what i am suggesting/speculating, is that the main dome-shaped shield itself could not stay operating with the power levels dropping, so it started shrinking in size, and as it retreated back over the outer sections of the city, forcefields went up to protect those sections, and eventually this shield failed leaving just the minimum shielding protecting the city from being flooded.
At these minimum levels, their effectivlly is no shield protecting the entire city, just these open sections, if the city was hit by a weapon, their is nothing protecting the closed metal structures, and damage would be done.

When McKay was talking about the shield being powered by the Nahquadah generators, he was referring to when they were underwater, since they didnt think the city could be brought to the surface. When they were on the surface, Weir asked if the shield could be powered for defensive purposes, McKay said no, but he didnt say weither or not the shield could be operated at minimum power levels as the did when underwater, without the weight of the ocean against them, it is likly that they could be powered in this way.

As you aptly said, all we can do is speculate, and that is all you can do as well. I saw the same episdodes you saw, and I have come to a different conclusion from you. All we are doing is speculating, I did notice one thing in Rising, McKay seems to use the words shield and forcefield interchangably, he said the forcefield holding back the ocean at one point, and later referred to the main shield, Grodin was talking about sections of the forcefield collapsing, and the computer was talking about the shield.

In the end, I think we are just going to have to agree to disagree, I do see where you are coming from, but I just dont agree with your PoV based on the evidence, but perhaps it will be cleared up in S4.

[Anubis-]

No doubt the Lanteans were smart enough to be able to figure out a way for Wraith weapons impacts to power it. However had they done that, then Atlantis would have always been safe, therefore no real drama or problems anytime the Wraith attacked. ZPM's provide the power, however are rare, so that means they have to be more careful.

I did not think so. Where the clue are left, that lantians got unlimited ZPM's? If it so, Janus would left few ZPM's left to Atlantis, so that Weir can replazed instead rolling them.

I think it would turn a lot of people off watching if everytime a Wraith fleet showed up & Shep & Co are laying about on sun loungers on one of the outside balconies watching the pretty colours of the Wraith weapons impacts on the shield. They'd always be safe as there would never be any problems of them running out of power, so there would be no drama. Realistically, they were smart enough to do so, & probably would have at least attempted it in real life, but for tv land, it would't be a good thing to have had them do.

What difference it make? Wraith are attacked Atlantis once, Asurans once (or twice, how it count that first one). Shield can not stop Asurans, so we got left only Wraith.

Allmoust 99% attacment are outside of Atlantis, middle of some primative nation.

And what I'm asking my friend, they allmoust are tired that "Some big are attacking earth (or in this case, Atlantis) and O'Neill safe earth some kind trick.". All my friend want back that sitution, where SG-team are explorers, not war after war. Maybe my friend represent minority opinion, you tell me, but I think that is more funny, if we see Sheppard & etc looking some new, not just war.

[Merlio]

Jebus Christ, what is it with some people around here!

In First Strike when they had the shield up, they still had a ton of ZPM power left. Therefore there was enough power still left for the shield to cover the entire city. If you disagree, then watch how they are able to take off using the Star Drive, as well as activate the shields & jump into HS. Couldn't do that without power!

Again I refer you to:



To it's minimum sustainable levels. It DID NOT collapse completely, it simply started shrinking itself in size to reduce strain on the ZPM. It sacrificed non critical areas to flooding so that main sections of the city could still be protected from the shield.

All areas that were not flooded were still protected by the shield (The main shield, the only 1 it has).

Then there is this:



or this:



or this:



As to your observations. Obviously the Naquadah genrators can't power any part of the shield no matter how small an area they want to cover because McKay says it in the episode.

"McKAY: We're working on that, but even with our most advanced naqahdah power generators, the equations are coming up far short."

They couldn't even power the deep space sensors or anything like that!

As for the bit about minimum levels, again your stating the obvious that really has nothing to do with the discussion. The shield only goes down to minimum levels when there isn't enough power to maintain the forcefield around the entire city. Therefore what does it take to be able to withstand enormos impacts on the shield.....You guessed it.....Energy!

Therefore the fact that it wouldn't have stood up to Wraith or Asuran attacks when working at minimum is kind the most obvious thing I've heard in a long while!

Lastly the areas that came up-unflooded were protected by the shield. The parts that were flooded were the sections that the main shield sacrificed.

Think of it a little like what happened in 'Revisions'. The dome had power issues, so it started sacrificing areas of the city to lessen the power drain. Meaning it could provide power for longer without toally failing. Only difference was that the dome wasn't under water.

So all this talk of secondary shields & the like is totally unfounded speculation on the fans part. There has never been any indication that it has any.

If it had backup shields, then why didn't they raise in 'The Return' after the Asurans knocked out the main shield.

Why didn't sections start bringing up forcefields to locked areas when the city put itself into lockdown in 'The Hot Zone'.

In 'The Long Goodbye' when Weir locked the city down completely, how come no force fields were raised like in 'Submersion' that prevented everyone from getting around the city.

So until secondary shields or internal forcefields or whatever are shown, then you may have cause to beleive it. However right now it's totally unfounded!

this guy is right.... there is only one shield, that simply changes in size depending on the amount of power, when it is low on power it just shrinks so small that it may seem like nothing more than a forcefield over the buildings...