Going up or coming down?

[Scorchijs]

The question is... which one of these things is more demanding from a Mobile Suit? Flying up all the way into space or performing an atmospheric re-entry?

I think, that the "coming down" part is more difficult. The high temperature, increasing gravity and all that... The Mobile Suit must be quite durable to endure that.
Anyway, your thoughts about this?

[Draco Starcloud]

I can't think of any Mobile Suit that can actually leave the atmosphere without some kind of ship or booster attatchment, so I'll say re-entering.

[Samster]

I'm not quite sure how to answer this question as very few MS are capable of atmospheric re-entry without some type of vehicle (eg. ballute system). I can't even think of any MS that were capable of reaching escape velocity on their own. So I guess what I'm saying is that atmospheric re-entry and reaching escape velocity are most times not dependent on the MS itself.

[mr.blonde]

i think the apsalus is able to do re-entry.

[Phantomexe87]

i think the apsalus is able to do re-entry.

Mobile Armors tend to be a completely different story though, their size allows them to utilize tehchnologies that let them do feats impossible for most mobile suits. I think the Zodiac and maybe some of Zanscares Mobile Armors have might have the ability for escape velocity. But for mobile suits, none that I can think of.

[Koshernova]

The Apsalus is meant to allow for both enough escape velocity to reach at least the upper atmosphere, as well as the intense friction of re-entry. I cannot think of any Mobile Suits that have that kind of thrust power, neither in UC nor the AU. Maybe the Messala, which has enough thrust to withstand Jupiter's gravity (according to the Suit's history, I'm unaware if the numbers match). But I still get the feeling even the Messala would need a booster of some sort.

On the other hand, while re-entry technology seems costly at best, it has been seen numerous times, both in advanced prototypes (the RX-78-2) as well as in mass-produced ballute packs for grunts.

So, according to animated evidence, I'd say re-entry is the easiest of both tasks. I'm unsure whether people here are using the term re-entry in the same sense I am using it: re-entering Earth's atmosphere.

On the other hand, I have to say, militarily speaking there is little reason for a MS to need to leave the atmosphere on its own. Think about parachute regiments. It makes sense that a plane drops them behind enemy lines, but they don't go all the way back by individually flying home (perhaps they rendez vous with another aircraft, and indeed in the UC we've seen MS tend to go back up to space in groups, carried by ships or shuttles).

[ORegan]

well, the only MS i can recall ever leaving earth to space were the God Gundam on Funnsiki foot pedestal thing, and the Tallgeese with the giant booster packs, but both of them didn't leave on their own strength, they either needed the help of giant engines or a horse to leave.

[toysdream]

I guess it depends what you mean by "difficulty." Only a handful of machines can launch into orbit under their own power, whereas anything can re-enter--all you have to do is fall down. Actually surviving re-entry is the hard part.

-- Mark

[Aegis]

I guess it depends what you mean by "difficulty." Only a handful of machines can launch into orbit under their own power, whereas anything can re-enter--all you have to do is fall down. Actually surviving re-entry is the hard part.

-- Mark

There just had to be a crack about that.

In all seriousness, seeing as the cast majority of MS couldn't reach space anyways without major assistance, be it a ship or a booster or whatever, while we've seen more MS manage to enter Earth's atmosphere on their own in one piece (which is still not alot but happens more often), I'd also say re-entry is the easier of the two, if only because it's something MS can actually achieve. Of course, when we do see certain mobile suits get lifted up into space with help from a ship, it just looks more... pleasant in comparison to the bumps and shocks of an atmosphere.

[razgriz]

neither is necessarily easier than the other, a mistake means u will just end up dying a different way
strike rouge needed a star destroyer lookin booster strapped to its a$$ to get into orbit so definitely no easy task to break gravity, and there r very very tremendous forces at work to keep you down to earth. case in point, shuttle challenger, while its booster exploded, the shuttle itself did not, but was gruesomely ripped apart by aerodynamic forces, when its structural integrity was compromised.

and obviously we are all well aware of the dangers of re-entry and improper heat distribution and angle of attack through various sci-fi, anime, and real life; shuttle columbia and a russian soyuz crash that killed all 3 cosmonauts

so i say its advantage: push

[OpMegs]

Well, it depends on what you mean by "demanding"

Structurally, exiting the atmosphere is probably easier on a mobile suit, as it's simply punching through ever lessening areas of atmosphere. Compare it to, say, football players running through banners and such at the beginning of a game, only make it multiple banners, with them getting progressively thinner from beginning to end.

Re-entry, by comparison, requires specialized equipment designed to allow a MS to survive the intense heat and friction and still be combat ready upon arrival. For instance, the ballute packs, waverider mode on the Zeta, the Archangel's liquid shielding, the Gamow class's detacheable entry pod, and the various four man drop pods ZAFT uses.

Performance-wise reverses this. Pushing one's way out of the atmosphere requires an incredible amount of thrust, and most mobile suits are unable to come even close to managing this. In Cosmic Era, it's even demonstrated that ships require external means to launch them into space.

Re-entry, however, as Mark pointed out, is relatively simple. Gravity is, after all, doing all the work.

[mr.blonde]

hey! i remmember that in endless waltz the wing zero did a re-entry, well the altron also did it.

[ORegan]

not to mention all the other gundams in the OVA as well as the tallgeeseIII. But they have the advantage of being made out of the indestructible gundanium, except for the TIII which is made of titanium alloy.

[ZeonfromHell]

I imagine a titanium alloy-built mobilesuit could be able to withstand atmospheric re-entry better than a steel-built one. Remember that the American space shuttles are all made of titanium-alloy and are built to withstand atmospheric friction without disintegrating or cooking their flesh-made internals (i.e. people). Although mobilesuits are essentially more fragile and complex than a little shuttle, I imagine a heavier, more robust mobilesuit built out of titanium alloy could handle it.

Escaping the atmosphere is a pain in the butt, though. The Karman line (dividing barrier between atmosphere and space) is about 50 miles or so above the surface of the Earth. No problem right? How about the force of gravity, which is -9.8m/s squared times the mass of the load? That requires a lot of thrust. Yes, some mobilesuits can do rocket-assisted jumps. But that would burn fuel way too fast. The only way I see that happening is a disposeable rocket-pack with enough thrust to offset the weight of a coolant tank and massive fuel tank, kinda like the space shuttles of today.

But another thing to consider is that ground-pounders have bigger thrusters and only pointed in a couple of directions (thanks to gravity). Space suits only need a set of small thrusters but in all directions. You really can't use one suit in the other environment (well, a space suit can operate on the ground I guess, but why bother when groundpounders can do rocket jumps and attack the essentially immobile-mobilesuit?). Why not just keep the groundpounders on the ground and the space suits in space? And if you are going to retrofit them to become the other suit, then why not just stick them on an HLV and move them in bulk? Moving one suit into space by itself just seems redundant to me.

[razgriz]

only if your kira yamato i think would you need to go into space alone, at least you know you would be somewhat ready for what awaits you. and you have a giant disposable booster.

[Wingnut]

I imagine a titanium alloy-built mobilesuit could be able to withstand atmospheric re-entry better than a steel-built one. Remember that the American space shuttles are all made of titanium-alloy and are built to withstand atmospheric friction without disintegrating or cooking their flesh-made internals (i.e. people). Although mobilesuits are essentially more fragile and complex than a little shuttle, I imagine a heavier, more robust mobilesuit built out of titanium alloy could handle it.

No, it couldn't. We've seen on more than one occasion even Gundarium armored MS not being able to achieve re-entry without help. Thus a normal Titanium MS wouldn't have any chance at all on its own without a balute pack or something to help it get through.

[ironscythe]

I would have to cast my vote for re-entry, and here's why:
When leaving the Earth's atmosphere, a spacecraft must only put out the bare minimum of thrust required to do so. It does not simply rocket away at full speed (I suppose this would depend on the spacecraft, though). The point is, the velocity is carefully controlled.

When making atmospheric re-entry, this is not the case. The spacecraft becomes a ballistic projectile, literally falling back to Earth. Re-entry speed is right around the terminal velocity for the spacecraft, and such speeds in the atmosphere produce enough kinetic friction between the spacecraft's hull and the air around it that the air ignites. Vibration is also a huge factor in re-entry, and can lead to stress fractures in the spacecraft's structure (as well as hydraulics, fuel tanks, etc). The heat is yet another factor, as we all remember from the Space Shuttle Columbia tragedy. Even the slightest weakness in the heat shielding on a spacecraft can lead to it completely disintegrating the moment it hits the atmosphere.

So yeah, re-entry is way more stressful on mobile suits (or anything for that matter) than orbital insertion.

[nacho-wan]

Say, do the Victory II can exit the admosphere by itself? It is stated to have about 20G of thrust, so it should suffice to left the admosphere... but having the frame support the heat involved, that's another story.

[Dr.G]

Well re-entry is of course the harder of the two operations. On a side note shouldn't all CE suits with PS armor be able to make re-entry? As long as they had full batts? In fact didn't Kira do that when he came down to JOSHA in the Freedom? Shoot the NJC should make entering the atmosphere cake.

[ironscythe]

Say, do the Victory II can exit the admosphere by itself? It is stated to have about 20G of thrust, so it should suffice to left the admosphere... but having the frame support the heat involved, that's another story.

Ugh...please remember that you're going pretty far into the future, and speculating about incredibly advanced technology when referring to Victory Gundam. For one, it has the Minovsky Drive, and can probably slow its own descent into the atmosphere considerably. Secondly, it is equipped with beam shields, which have been shown to effectively resist all kinds of punishment from advanced particle weapons. How much thrust it has doesn't even factor into the equation.

Well re-entry is of course the harder of the two operations. On a side note shouldn't all CE suits with PS armor be able to make re-entry? As long as they had full batts? In fact didn't Kira do that when he came down to JOSHA in the Freedom? Shoot the NJC should make entering the atmosphere cake.

My philosophy: don't even try to think about CE technology from a physics standpoint. The laws of physics are only applied if they don't interfere with the plot. And even then, they're bent horribly.