Colonial Chrome

I think, that there is a force field, that prevent each hangar on a ship to be presented zo the vacuum.
But: Does this "Hangar Shield" only protect from energy and hold "the air" in? How can it control the pressure, when fighters or transports flying out or in? Why can enemy fighters can fly in an hangar? Could a shield be calibrated to prevent an enemy escaping from hangar? (like the Falcon in SW IV)
We know, that a ISD can catch a corvette. From "ISIS Coordinates" we CAN think, that there is air and normal pressure. SW IV is another "proof" of that.

*thinking*

And yet in Episode III, Anakin and Obi-Wan were unable to land in the Invisible Hand because the (presumably hanger's, since we were shown the hanger shield being blown out) shields were still up. Apparently this wasn't the same shield as had been protecting the ship itself, since I believe that was down already (I'll have to reread the novel).

So does this shield then allow only launches and no landings? Can it be configured to do both? What prevents an enemy from landing in the bay (shield frequency matches, perhaps)?

OK, firstly, only canon information is relevant to Chrome, so that's ONLY the movies. Chrome does not condone, support or encourage any contact with the EU or third party sources.

Hangar shields have been shown many times, it is only in RotS that we have the suggestion that ships can't necessarily fly through them.

The exchange goes something like -
"There's General Grievous' flagship, the one crawling with vulture droids."
"oh, great. Well, have you noticed the shields are still up?"

As far as Chrome is concerned hangar shields are generally set to repel with a given amount of force. This repulsion happens both ways. If you set the power to work at around 1.5 atmospheres, the air will stay in (As it exerts less pressure than this) but anything else ought to be able to push through.

In a combat environment you can increase that power much higher. If you have, say one hundred atmospheres, then a fighter can still fly through it, but the deceleration shock would be very high, and almost certainly destroy the ship. In a tense environment it's quite difficult to tell what setting the shield is on, so in RotS they opt to simply destroy the shields entirely.

Controlling this doesn't seem to be a complicated question - your deck chief has command authority. It seems probable there's a button, or perhaps a switch or two.

As soon as people start talking about frequencies and harmonics, they've gone Trek. Star Wars doesn't do that kind of thing.

In ANH the Tantive IV is boarded by a shuttle, so there's no exposure to vacuum outside the ship. AFAIK an ISD cannot pressurise either of the main bays. Short of canon evidence, and with no features to suggest otherwise, Chrome says they cannot.

Sounds reasonable. So the fighters could launch knowing what their speed had to be to punch through and not go out in a display of fireworks, but enemies would have no knowledge of the specific setting, so they'd be out of luck.

Yeah, I mean it would probably be even simpler in most cases. Green light over the hangar (And thus not visible from outside) and you go, red light, you don't go. Or traffic controllers doing go / nogo gestures. You don't need to overcomplicate things.

"Tower, Black seven six request clearance for launch."
"Black seven six cleared for launch main bay, departure track one, clear skies."

All kinds of cool military jargon develop from knowing if the shields are rigged for defense or flight ops.

"Tower, Black Seven Six on final track three, bingo fuel."
"Black seven six, tower, call the ball."
"Black seven six has the ball, ball is green."
"Confirm ball is green."

All that stuff. Good fun. Everyone knows what calling the ball is, yeah?

Also, passing through the field would cause damage proportional to speed, so slowly launching fighters could push through 'thick' shields, fast moving attacking ships would get smashed.

The main trouble with this model is that Nooki Noo gets his nubian fighter in through the battleship's shields in TPM. I'm forced to assume that Anakin knew he could fly through thanks to that Jedi forseein' trick.

Maybe there wasn't any atmosphere. There would be no need to, droids can't breath. Just gravity. Then there would be no need for hanger shields, and I doubt the Trade Federation was careful enough to recognize the threat (does this sound familiar) of a one-person starfighter.

There's definitely atmosphere - Nooki Noo Skwakky Wakky and Ob Nob Kenebnob walk around in the hangar talking without the whole suffocating to death thing.

As to why, yes, it does seem odd that they have a large pressurised hangar when Seperatist fighters are droids. However, we do see that the vulture droids inhabit the exterior of the ship, and we can guess that the main bay is in fact more of a utility hangar than anything else, used for shuttles etc, and therefore used by the organic crew that are normally aboard. Recall that both Grievous and Tyranus are on board, and they both need air to some degree, even if GeeGee can survive for a while without.

It may be worth observing that the TF battleship in TPM also is pressurised despite the population being mainly droids.

I would argue that these ships are not designed for a droid crew, or at least not exclusively, and Star Wars Tech allows them to be pressurised with clean air at zero or near zero effective cost.

I take the point of ignoring the single fighter, we see that in the Battle of Naboo as well, of course. In the case of RotS we have solid dialog stating that there would be great difficulty in breaching a shield secured ship, so we have to take that as solid prima facie. Perhaps the Seperatists learned something from Nooki Noo after Naboo. Certainly I assume that Nooki's success at Naboo is the main motivation behind his concern at the fighters in ANH.

I meant in TPM and not ROTS. ROTS, we can clearly see the atmosphere venting from the hanger as the physical doors slide shut, so there's atmosphere in there. In TPM, there's no evidence that there is atmosphere, since the only inhabitants are droids and while there is gravity, there's no organics walking around there.

But I guess that's just arguing semantics. Like you said, the Federation might have (*GASP*) actually learned from Anakin after he blew up their Droid Control Ship in a beautiful fireworks display.

We do know that it is at least possible to have the hangar bays of a Lucrehulk be pressurised as Ob Nob and Quinky Gin walk through it untroubled as they find transports to hide away on.

Given that this is a droid logistics area, if THAT bit is pressurised, one might assume most or all of the ship is.

Also note how the battle droids in TPM seem to push their way through the Gungungungun's shield, it does not stop physical things like it does energy it just takes a bit more of an effort ("The slow blade penetrates the shield")

Shai hulud!

What about a magnetic field?

In the ANH you hear in the background when the Falcon is being brought aboard the Death Star, "Clear Hangar Bay 327, we are lowering the magnetic field." Now I dont remember that much about my physics course but couldnt a magnetic field hold in the atm. or was this an added layer of protection for the Death Star?

The Death Star has several magnetic shields in place, we also hear Red One saying 'Passing through the magnetic shield, shields double front."

Magnetic fields couldn't hold the atmosphere in unless that atmosphere was ionised. An ionised atmosphere wouldn't be breathable, so it can't be that. I'd suspect the magnetic shield is essentially the first line of defence to stop ships entering, as they're made of lots of metal.

I just watched Ep. 1, and I'm pretty sure that I can see a couple of Vulture fighters leaving the hanger at the same time Anakin flies into it. I can't be positive, because the DVD player I have is no good at the whole pause/slow forward thing, but...

Could there be more than one type of shielding over a hanger entrance? Or maybe a couple of "settings" for one shield?

I know that I'm new and all that, but here's my thought on the issue.

In RotS, the "shields are still up" are in reference to the main defensive shields. I'm thinking that there are two types of shields for most of the battleship hangers. The environmental shielding (which holds in the atmosphere) and the defensive shielding (magnetic shielding and the like). In ANH the environmental shielding remained in place, while the defensive shielding needed lowering in order to bring in the ship.

It's been a while since I've seen TPM, but I think the comment that there were Vulture Droids leaving at the same time that Annie was flying in was the reason he could get through the defensive screen without a problem. The Defensive Shields were lowered momentarily to allow the Vultures to exit the Hanger Bay.

Also, I think most ships have an atmosphere through out the ship, even if they're droid heavy in crew. If something goes wrong and you need a biological maintenance member, or to greet incoming ambassadors or Jedi, it would be too time consuming to bring up an appropriate environment every time that the ship came or went.

I like the Admiral's statement that there is a "near zero" energy method of maintaining atmosphere. It makes sense, since that would be one of the first things developed in most space faring cultures, in my opinion.

I don't think so, the narrative continuity is pretty direct (I'm watching the sequence as I type,

"Well, have you noticed that the shields are still up?!"
"Sorry, Master..."
Anakin blasts gadgets right by the door, the blue lights splutter and go out, atmosphere starts rushing out, and the emergency blast doors close.

In cinematic terms this is fairly simple - the shields Obi-Wan refers to are the shields that Anakin disables, so the ones that retain atmosphere in the hangar. The fact that these shields are a problem for the two Jedi Fighters would indicate that these shields either both retain atmosphere and screw up ships entering, or there are two kinds of shield at the same time, but certainly, we're talking about the hangar shields, not the primary shields.

As an aside, it seems to me that starship shields, on the order of capital ships, are set a surprisingly long way from the hull - capital ship combat seems to take place mainly within the perimeter, with cannonades simply pounding the bejesus out of each other's armour. This may well be why the Death Star's field is so far out...



That that is the sort of opinion that needs backing up - what figures are you using to estimate repressurisation?

In anycase, if we're talking about, for example, Lucrehulk ships, then we know there's a command orb in the middle, and cargo arms forming the bulk of the ship. I think it wouldn't be at all unreasonable to assume that under most circumstances the arms are not pressurised. Normally biological visitors would go directly to the Core Ship. The DCS that recieves the Jedi Delegation could well have pressurized a section to accomodate the Radiant VII, which may have been too large to dock with the Core ship itself.