Stark's Arc Reactor Fuel Consumption

[Havok]

There are two arc reactors. One in the suit, one in Tony's chest. I don't think Stark is the type of guy to make one not have enough power to power the suit.

It's possible that the newer suits, having their own reactors, no longer have a way to pull power from the one in his chest.

Yes, because Tony Stark likes to UNDER-engineer things.

As for a space suit... well being in space I'm assuming that Stark no longer has to worry about pollutants or radiation or anything like that like he would in an atmosphere so he may have far more options for propulsion that just wouldn't be feasible or safe otherwise. Like the Arc reactor, it all just becomes a matter of miniaturization.

[Napoleon the Clown]

He's Tony fucking Stark, if anyone can give ion drives enough oomph to produce large amounts of thrust, it's him. It would take very, very little xenon (relatively speaking) to give him lots of delta-v.


Though as far as needing air, he does use it underwater. So either it can put water to use, too, or it doesn't need air for basic operation. Now, to dispose of waste heat...

Problem of space is getting rid of excess heat, since there's nothing to pick up the energy. How plausible is the idea that his suit, or the reactor, is designed to shut down if heat builds up too much? He's been going all-out throughout the entire battle, so it may well have been getting really damn close to begin with. Then he grabs the missile and puts as much power to use as he possibly can, giving the missile a free trip to space. He continues pushing his suit as hard as possible right into what may well have been a vacuum and without that little bit of matter around it, it overheated enough to force a shutdown. Reason for even having a function like that: He never figured he'd put himself in a situation where he was in for a several thousand foot drop if it did overheat. IIRC, most of his most energy-intensive battles have seen him either on the ground or close enough to it that he wouldn't turn gelatin if he lost power. That suit is durable as hell, so most of the time he'd be okay for a couple minutes as it bled off enough heat to be safely functional again.

Or it could straight up be a factor of the Arc reactor that he can't do much about. He'd love to set it up so it can overheat in a pinch, but the physics of how it operates simply don't allow that. The reactor may utilize a superconductor that does its thing at temperatures well beyond what anything we have in the real world can achieve, but loses superconductivity over a certain temperature. Once you get a meaningful amount of electrical resistance, the Arc reactor can't operate terribly well.



I mean, yeah, his suit not being able to operate in a vacuum is reason to assume it needs air (or water) to function properly. But that doesn't really explain why he lost power entirely.

[Lord Revan]

Well we saw what happens to an Arc Reactor if it overloads in Iron Man, it could be that Stark thought that auto-shut down to reboot would be a safer option then blowing a hole in his torso, for all we know the only reason the armor didn't reboot properly was the massive battle damage it had taken before.

[Simon_Jester]

There are two arc reactors. One in the suit, one in Tony's chest. I don't think Stark is the type of guy to make one not have enough power to power the suit.

It's possible that the newer suits, having their own reactors, no longer have a way to pull power from the one in his chest.

Yes, because Tony Stark likes to UNDER-engineer things.

Well, Tony may not have wanted to put an uprated arc reactor into his chest to replace the one that was in there at the end of Iron Man II; he may have upgraded in that way. Also, he may have wanted to ever have to deal with the problem he faced in the first movie, with the suit draining power he needs in order to not die.

Though as far as needing air, he does use it underwater. So either it can put water to use, too, or it doesn't need air for basic operation. Now, to dispose of waste heat...

If the suit works by using the repulsor beams to push against the surrounding medium, that would work underwater.

Problem of space is getting rid of excess heat, since there's nothing to pick up the energy. How plausible is the idea that his suit, or the reactor, is designed to shut down if heat builds up too much?

Perfectly plausible, it just seems like the suit wasn't space-capable at all, but your explanation might well be the one.

I mean, yeah, his suit not being able to operate in a vacuum is reason to assume it needs air (or water) to function properly. But that doesn't really explain why he lost power entirely.

Well, it suggests he physically ran out of power during the battle, separate from or in addition to the suit failing to work in vacuum.

[TOSDOC]

I forgot about the underwater scene--that adds a whole new dimension. Repulsors work fine there, then he switches to thrusters once he's cleared the surface. And the water acts as a fine heat sink.

But the suit is sealed like a hard dive suit, since from the way he's speeding up to the surface Stark certainly isn't feeling a need to decompress and avoid an embolism. I'd feel too much like it was shifting goal posts to say that that the Mark VI can go underwater while the Mark VII was just built for air combat, when it's just as likely the Mark VI and VII will both work well underwater, but in IM3 Stark will demonstrate his propensity for building more specialized suits. He could have added an external air source for his quick trip underwater. But it would also make sense that no matter what suit he was in, he'd want to be able to breathe and function in multiple hostile conditions, such as immersion, fire/smoke, poison gas, dust storms, or high altitudes and increased g-forces. Remember, he's Tony Fucking Stark!

Then, both suits being equal, I can't for the life of me explain why he passed out in space. If the Mark VII was solely designed for use in air it makes sense. Then it shuts off and he passes out for lack of air. But having a sealed suit against the outer environment means he shouldn't have passed out even if the suit shut off--unless he's still brainstorming this as he goes, he should have a way to have oxygen delivered to him even if the suit's off.

But if he ran out of power, why is he still alive? The only explanation there is that the arc reactor in the suit ran dry, not the one in his chest, and he just refueled the suit on the way up the tower to grab Loki.

[Simon_Jester]

If the suit is normally designed to be airtight, combat damage may have caused it to stop being airtight. Ideally there'd be visible evidence of air rushing out of the suit or vacuum exposure, but you really can't have everything.

[TOSDOC]

If the suit is normally designed to be airtight, combat damage may have caused it to stop being airtight.

I'll take it.

but you really can't have everything.

That'll be on this thread's tombstone.