Weaknesses of the AT-AT

[StarSword]

This has been bugging me for a while.

In their sole onscreen combat encounter in The Empire Strikes Back, AT-ATs are bad-ass pieces of machinery able to blow away artillery pieces, unshielded airspeeders, and even an entire shield/power generator complex (I hear differing reports as to what the "generator" was generating) in single shots, and the only way to bring them down was by tying up the legs so the thing fell over, or by throwing a thermal detonator (I think) through a hatch into the engine room.

This has become a serious brain bug in some parts of the Expanded Universe, most notably in the video games where the only way to stop an AT-AT is to do that time-consuming T-47 snowspeeder-with-towcable trick, or to run underneath it with a grappling gun and throw a grenade into the engine. Even when dedicated bombers like the Y-Wing are available (Rogue Squadron II: Rogue Leader, "Vengeance Kothlis"), you still have to waste time switching to the damn T-47 when the Imps send out the AT-ATs. This is in direct contrast to a scene in Isard's Revenge, where they conclusively demonstrate that you can bring down an AT-AT in other ways:

Hobbie, her wingman, came in on a crossing path that gave him a clean shot at the tail. Lyyr's shots had slagged armor on the mechanical beast's flank, but hadn't done any serious damage. Robbie's attack ran from below the AT-AT's body on up the back, and at least one shot holed the fuel tank. Flaming fluid streamed down like a tail, and then an explosion ripped the walker's back end open. The blast pitched the walker up into the air and through a somersault that landed it on its back. The massive legs telescoped down into the body, and then tore free. The walker's armored head slammed into the snow-covered ground, cracking armor plates, and started leaking smoke.

Tycho growled over the comm channel. "Running on the next one. Decap shot."

Wedge nodded. "On your tail."

Tycho brought his X-wing down in a dive, and then leveled out ten meters. Coming in at shoulder height on the walker, Tycho banked right to run from tail toward the head, and then snaprolled his ship level and hit right rudder. The X-wing's tail skidded toward the left, bringing its nose in line with the walker. Tycho's first cycle of shots vaporized armor on the walker's body, but the second quartet blasted away at the joint of the flexible neck and the body itself.

Wedge marveled at Tycho's soft hand on the X-wing's stick. He followed him into the dive, but rolled out right and cut his throttle back. The walker had begun to turn to its right, so Wedge's roll put him on a direct line with the AT-AT's head. He nudged the aiming reticle over the walker's head and pulled the trigger.

A stuttered quartet of bolts hit the walker. Two glanced off, leaving long scars on its forehead, but the other two pierced the transparisteel viewports on the pilot's compartment. Fire exploded back out, and the walker slowly started to sag forward. Its chin slammed into the ground, and then the body's weight snapped its neck.

"Easier ways to decap it, Wedge."

Wedge throttled up and banked starboard into a climb. "Sorry, didn't have time to consult with Ewoks to find out how they'd handle the situation." He glanced down at his chronometer. "No time to be fancy on the other two, just swarm them."

I'm not disputing that AT-ATs are devastating weapons, but they have any number of weaknesses an adversary can exploit.

• Blind Spot: The single biggest weakness of the AT-AT design is a blind spot you could fly a Death Star through. Their only weapons are mounted on the head, which can only fire in a cone pointed directly forward. In addition to not being able to see behind them (rear-view mirrors, anyone?), they can't shoot anything that comes in close. This enables exploits like the (in)famous towcable trick*, and Maj. "Hobbie" Klivian's "up-the-kilt" shot to the fuel tank in the previous passage.
  Now, Darth Wong points out that the AT-AT relies on ground troops and smaller vehicles to protect its flanks, but would it really have been so hard for them to include a few repeating blasters on swivel mounts? The Empire has no shortage of cash (or manpower, if such weapons would require a gunner). Hell, even the Millennium Falcon mounts a swivel blaster for precisely this purpose!
  But the AT-AT mounts no tailguns, no belly guns, and no dorsal guns. It relies solely on its forward-facing laser cannons.
• All Line-of-Sight Weaponry: Admittedly this wouldn't have been useful in TESB, since the battle took place on a flat glacial plain, but some form of parabolic-arc weaponry would be extremely useful in situations where the enemy is, say, on the other side of a hill taller than the AT-AT. (As per Darth Wong, this is the main reason, engineering-wise, that they are so tall.)
• High Center of Gravity: Admittedly this one is suspect at best, and Darth Wong does a fine job of refuting it on the main site, but it remains that the AT-AT's center of gravity is high enough that with sufficient force, one can knock it over. (I wonder if an AT-TE's main cannon could do it?) By contrast, a typical tank is broad and flat, so you need some form of leverage to flip it.
  Of course, an AT-AT weighs so much that such force is as likely to smash the walker outright than just knock it over, but...
• Get a Bigger Gun: Okay, not really a weakness specific to the AT-AT, but I've always wondered why Gen. Rieekan stuck Rogue Squadron, the best starfighter unit in the Alliance, in what amounts to glorified airspeeders for the duration of the Battle of Hoth. Quite apart from the fact that putting twelve pilots into two-man speeders cuts the number of combatants in half, Isard's Revenge demonstrates conclusively that direct hits from starfighter-grade laserfire can reliably bring down AT-ATs. If there were no spare X-Wings, that would be justification, but Luke has one available when he leaves Hoth at the end of the battle. Was this honestly the first time the Rebels had engaged AT-ATs?
  Point is, if the T-47s' blasters can't penetrate the armor, then screw the T-47s and bring the Y-Wings and X-Wings into the picture!

* This trick was actually foreseen well before A New Hope, as seen in a passage in Tales from the Mos Eisley Cantina where Col. Maximilian Veers (the "General Veers" of TESB) shoves a promising young AT-AT pilot into the stormtrooper corps for suggesting this very exploit.

[PhilosopherOfSorts]

Yeah, we've been over all of this before, and come to the conclusion that the AT-AT was origanaly meant to be a long range assault gun, which is why its so tall, but the Emperor saw the design and said "I like it, make it a troop carrier, too." This caused all manner of design compromises, leading to the flawed vehicle we see.

That or everyone in the Imperial military is retarded.

[StarSword]

Okay. Sorry to dredge up an old topic.

EDIT: I was mostly complaining about how video game designers made the AT-AT indestructible unless you do the towcable thing. But this probably isn't the right place for that.

[Simon_Jester]

In a number of Star Wars RTS games, AT-ATs are merely very tough to kill- not indestructible. You mostly see indestructible AT-ATs in the fighter-oriented games, where "looping" the AT-AT is mostly just a specific challenge to break up the monotony of flying around shooting lasers at things.

On a side note, there's a trivially obvious counter to the towcable trick. Just stop walking. No amount of tying an AT-AT's shoelaces together can make it fall over if it doesn't move. Wait for one of your buddies to cut the cable- this can be done with light antipersonnel fire against the legs, for example.

[Boeing 757]

I'm not disputing that AT-ATs are devastating weapons, but they have any number of weaknesses an adversary can exploit.

More over, their design has the added disadvantage that it's slow as molasses. I mean, with the speeds at which we saw them advancing during the Hoth-assault, I doubt highly that they're capable of the 60 km/h given to them by WEG...unless they can power-walk or some thing.

Yeah, we've been over all of this before, and come to the conclusion that the AT-AT was origanaly meant to be a long range assault gun, which is why its so tall, but the Emperor saw the design and said "I like it, make it a troop carrier, too." This caused all manner of design compromises, leading to the flawed vehicle we see.

That or everyone in the Imperial military is retarded.

I also like the idea that the AT-AT's ultimate function is to be a weapon meant solely to inspire fear as a part of the Tarkin-doctrine. This is what the SW:VD has to say about them:

These gigantic machines are used as terror weapons. Their powerful walking controls can only be operated by pilots of great physical strength. Until the Battle of Hoth, AT-ATs were widely regarded as invincible in combat, and their mere appearance was often enough to drive enemy forces into fearful retreat.

Considering that the Galactic Empire enjoys an immense technological and resource superiority over most every one in the GFFA, AT-ATs can afford to have most of these weaknesses while they plod along scarring the shit out of enemy ground troops.

[Formless]

I think the very idea that the AT-AT is a troop transport itself is a retarded brainbug. It certainly didn't serve that role in the original movie-- when Veers finally blows up the rebel shield generator with his walker's main guns, he doesn't drop his tank to its knees and send out stormtroopers (and really how else are the troops supposed to get out? Climbing ropes?). He calls up Vader who is waiting in orbit and tells the Dark Lord that it is safe to land troops. I don't know at what point the EU gave it the secondary role of ferrying soldiers across the battlefield-- the earlier video games like Rogue Squadron and Star Wars Rebellion (aka Supremacy) both treated it as a heavy tank. If I had to guess, though, it would probably be whenever it picked up its current idiotic name-- again, the movie simply referred to them as "Imperial Walkers" which is all you really needed to know.

[YT300000]

[*]Get a Bigger Gun: Okay, not really a weakness specific to the AT-AT, but I've always wondered why Gen. Rieekan stuck Rogue Squadron, the best starfighter unit in the Alliance, in what amounts to glorified airspeeders for the duration of the Battle of Hoth. Quite apart from the fact that putting twelve pilots into two-man speeders cuts the number of combatants in half, Isard's Revenge demonstrates conclusively that direct hits from starfighter-grade laserfire can reliably bring down AT-ATs. If there were no spare X-Wings, that would be justification, but Luke has one available when he leaves Hoth at the end of the battle. Was this honestly the first time the Rebels had engaged AT-ATs?
Point is, if the T-47s' blasters can't penetrate the armor, then screw the T-47s and bring the Y-Wings and X-Wings into the picture![/list]

Maybe the presence of the shield keeps both sides from being able to field flying machine other than repulsorcraft? Certainly the Imperials didn't send down any TIEs or shuttles until after the generator was down.

[Purple]

I think I can provide a plausible explanation for the combination. The AT-AT is not an IFV, it is a strategic transport coupled with an assault gun but it is not a tactical transport. Think of it this way. You have a platoon of 40 men, several light walkers/repulsorlift tanks for close support and finally the AT-AT. The AT-AT seems to be designed to bring infantry to the edge of a combat zone (several km away from the actual battle) and deploys them. After that it stands back and fires away like an infantry tank whilst the rest of the formation closes in. If wookipedia is to be believed they carry a platoon worth (40 men). And that along with the long range firepower is clearly indicative of such a role.

The closest modern equivalent I can think of is having a truck transport your infantry and towing a gun. The truck stops and the infantry dismounts to go on and fight while the gun and truck stand back and provide artillery cover.

[The Romulan Republic]

Hmm, they actually kind of make sense in that role.

Still a flawed design, but sort of comprehensible.

[Vehrec]

[*]Get a Bigger Gun: Okay, not really a weakness specific to the AT-AT, but I've always wondered why Gen. Rieekan stuck Rogue Squadron, the best starfighter unit in the Alliance, in what amounts to glorified airspeeders for the duration of the Battle of Hoth. Quite apart from the fact that putting twelve pilots into two-man speeders cuts the number of combatants in half, Isard's Revenge demonstrates conclusively that direct hits from starfighter-grade laserfire can reliably bring down AT-ATs. If there were no spare X-Wings, that would be justification, but Luke has one available when he leaves Hoth at the end of the battle. Was this honestly the first time the Rebels had engaged AT-ATs?
Point is, if the T-47s' blasters can't penetrate the armor, then screw the T-47s and bring the Y-Wings and X-Wings into the picture![/list]

Maybe the presence of the shield keeps both sides from being able to field flying machine other than repulsorcraft? Certainly the Imperials didn't send down any TIEs or shuttles until after the generator was down.

X-wings have repulsors, but that's not the real issue. The real issue is that this guy expects us to believe that Isard's Revenge makes the rebels look like idiots. I'd prefer to believe differently-that Isard's revenge is subordinate canon and can in fact be wrong about X-wings demolishing AT-ATs with their lasers. If they were so powerful, why not dismount one or a dozen and have an unstoppable anti-tank battery of firepower from concealed positions? Occam's Razor would seem to suggest to me that if X-wings weren't used against the walkers then they wouldn't have been much more effective than the low altitude airspeeders that actually fought the battle.

[StarSword]

More over, their design has the added disadvantage that it's slow as molasses. I mean, with the speeds at which we saw them advancing during the Hoth-assault, I doubt highly that they're capable of the 60 km/h given to them by WEG...unless they can power-walk or some thing.

Maybe it's not a question of the AT-AT not being able to travel faster than 10 km/h. I think it's more a question of its supporting ground troops not being able to go faster than that during combat. Remember that because of its enormous blind spots, it has to rely on infantry and smaller vehicles to keep its flanks and belly protected against, say, Luke Skywalker with a thermal detonator. (Presumably the Rebel ground forces had already stripped that walker of its escorts.)

The short story "When the Desert Wind Turns" in Tales From the Mos Eisley Cantina follows the early career of an Imperial recruit named Davin Felth. In one sequence, he tries out as an AT-AT operator, and gets the chance to take one for a spin at Carida Academy. The AT-AT gets out of the city and into the countryside at a very fast loping trot, where the instructor begins the simulation which results in Felth's predicting the towcable attack (and his being shoved sideways into a stormtrooper suit by Col. Veers to cover up said design flaw).

Considering that the Galactic Empire enjoys an immense technological and resource superiority over most every one in the GFFA, AT-ATs can afford to have most of these weaknesses while they plod along scarring [sic] the shit out of enemy ground troops.

Oh yes, they were definitely designed for psychological impact. (Kinda hard not to be scared of a behemoth that knocks pieces out of the ceiling from footfalls at least a dozen klicks away.) I'm not clear on one of your terms, though: what's "GFFA" stand for?

Maybe the presence of the shield keeps both sides from being able to field flying machine other than repulsorcraft? Certainly the Imperials didn't send down any TIEs or shuttles until after the generator was down.

Possible, but I doubt it. Based on scenes in the EU (including a paragraph a page or two after the passage I quoted from Isard's Revenge), despite the aerodynamics of the X-Wing it relies partly on its repulsor coils to stay aloft during atmospheric combat. And TIEs would be even more reliant on repulsors, since they have no aerodynamics at all. (This is a big reason X-Wings win against TIEs nine times out of ten in atmo: they're less affected by crosswinds.) Unless the T-47 uses an entirely different repulsor technology than the X-Wing (unlikely since they're both Incom designs), what's bad for the goose is bad for the gander.*

The lack of Imperial air support suggests to me that the Rebel base's deflector shield was similar to the Gungans' in TPM: an umbrella that blocks fast-moving objects (and presumably energy weapons, since the Imps didn't bother with an orbital attack). So the Imps landed ground forces outside the shield, then pressed through it.

It could also have a climatic explanation. It's stated in both TESB and the Guide to Vehicles and Vessels that the Rebels had to extensively modify the T-47s for them to function properly in Hoth's eternal winter. Maybe starfighters can't function long enough in Hoth's weather to be useful. (Real-life aircraft have trouble with icing, too.)

I'd prefer to believe differently-that Isard's revenge is subordinate canon and can in fact be wrong about X-wings demolishing AT-ATs with their lasers. If they were so powerful, why not dismount one or a dozen and have an unstoppable anti-tank battery of firepower from concealed positions? Occam's Razor would seem to suggest to me that if X-wings weren't used against the walkers then they wouldn't have been much more effective than the low altitude airspeeders that actually fought the battle.

Um, who would be dismounting? I'm a little confused.

I'll admit that the EU books are subordinate canon. (Yes, I've read the canon explanation: if book and movie conflict, movie wins.) But for the record, they didn't actually penetrate the AT-ATs' plating in Isard's Revenge (and I'm sorry if I made it sound like they did); all the killshots in that scene were aimed at weak spots like the hip joints, fuel tank**, neck, and cockpit.

To be fair though, information I've discovered since my last post (such as at the Star Wars wiki) suggests that Hoth actually was the first time the Imperials had deployed AT-ATs against the Rebels, and therefore the use of T-47s could be chalked up to inexperience (or the aforementioned weather problem). And by the time they realized their blasters weren't doing anything useful, they didn't have enough time left to switch to something more effective (the Imps were closing on the shield generator), and Luke came up with the towcable exploit.

By contrast, Isard's Revenge takes place (six?) years later, and evidently dealing with AT-ATs has become old hat for the New Republic since the Rogues hardly bat an eyelash before butchering four of them.


All this is mostly my being mad that the designers of Original Trilogy fighter games like Rogue Squadron invariably force you to use the towcable trick on AT-ATs, which was a stopgap measure Luke came up with on the spur of the moment. I'd rather do like Wedge and blow the lid off the cockpit, frankly: seeing a walker faceplant is amusing, but seeing its head blow up is infinitely more satisfying.

* Yeah, I butchered a cliche. Sue me.

** I wonder how much force that fuel explosion exerted if it sent the AT-AT for a somersault.

[PhilosopherOfSorts]

X-wings have repulsors, but that's not the real issue. The real issue is that this guy expects us to believe that Isard's Revenge makes the rebels look like idiots. I'd prefer to believe differently-that Isard's revenge is subordinate canon and can in fact be wrong about X-wings demolishing AT-ATs with their lasers. If they were so powerful, why not dismount one or a dozen and have an unstoppable anti-tank battery of firepower from concealed positions? Occam's Razor would seem to suggest to me that if X-wings weren't used against the walkers then they wouldn't have been much more effective than the low altitude airspeeders that actually fought the battle.

They probably didn't have enough fighters that they could dismount the weapons like that, at least, not at Hoth. Remember, fleeing rebel transports only got two X-wings each as a fighter escort, that tells me they were in short supply.

[The Romulan Republic]

The lack of Imperial air support suggests to me that the Rebel base's deflector shield was similar to the Gungans' in TPM: an umbrella that blocks fast-moving objects (and presumably energy weapons, since the Imps didn't bother with an orbital attack).

Presumably nothing. It is actually explicitly stated in The Empire Strikes Back by one of the Imperial officers that the Rebel shield can stop an Imperial bombardment.

[dworkin]

I always felt the walkers were shiny new improved versions with extra armour. The rebels fully expected their weapons to work. The armour was just 'too strong' and that was a big suprise. Fully consistant with the main theme of the movie.

As for why the Empire uses walkers. Lucas wanted a reinactment of the 'Battle of Woking'. I feel he did very well in that regard.

[StarSword]

The lack of Imperial air support suggests to me that the Rebel base's deflector shield was similar to the Gungans' in TPM: an umbrella that blocks fast-moving objects (and presumably energy weapons, since the Imps didn't bother with an orbital attack).

Presumably nothing. It is actually explicitly stated in The Empire Strikes Back by one of the Imperial officers that the Rebel shield can stop an Imperial bombardment.

Ok, yeah. I plain forgot that remark.

[Metahive]

I think the very idea that the AT-AT is a troop transport itself is a retarded brainbug. It certainly didn't serve that role in the original movie-- when Veers finally blows up the rebel shield generator with his walker's main guns, he doesn't drop his tank to its knees and send out stormtroopers (and really how else are the troops supposed to get out? Climbing ropes?). He calls up Vader who is waiting in orbit and tells the Dark Lord that it is safe to land troops. I don't know at what point the EU gave it the secondary role of ferrying soldiers across the battlefield-- the earlier video games like Rogue Squadron and Star Wars Rebellion (aka Supremacy) both treated it as a heavy tank. If I had to guess, though, it would probably be whenever it picked up its current idiotic name-- again, the movie simply referred to them as "Imperial Walkers" which is all you really needed to know.

Problem is the AT-AT fails even harder as an MBT than as a troop transport. In the latter role there's at least a sliver of justification for the huge "belly" and why the weapons are fixed forward. As for how the troops leave the transport, well, in EAW they indeed fastrope out of it. Also, if IIRC Veers' AT-AT did have snowtroopers on board in ESB.

In SW: Rebellion a picture of AT-ATs was used to represent entire army regiments, so you can't consider this to be an endorsement of its role as a heavy tank.

[Simon_Jester]

I think the very idea that the AT-AT is a troop transport itself is a retarded brainbug. It certainly didn't serve that role in the original movie-- when Veers finally blows up the rebel shield generator with his walker's main guns, he doesn't drop his tank to its knees and send out stormtroopers (and really how else are the troops supposed to get out? Climbing ropes?). He calls up Vader who is waiting in orbit and tells the Dark Lord that it is safe to land troops. I don't know at what point the EU gave it the secondary role of ferrying soldiers across the battlefield-- the earlier video games like Rogue Squadron and Star Wars Rebellion (aka Supremacy) both treated it as a heavy tank. If I had to guess, though, it would probably be whenever it picked up its current idiotic name-- again, the movie simply referred to them as "Imperial Walkers" which is all you really needed to know.

A lot of the secondary sources insist on having troops inside the AT-ATs. It doesn't make a lot of sense to me either because, as you say, it's hard to deploy troops from something like that.

But AT-ATs have been called that for years, probably since the Star Wars toy marketeering of the 1980s, and certainly since around 1990 when the first (some of the first?) EU novels were coming out. Not a new name.

And it does at least explain how you wind up with a platform that is nominally a heavy tank with troop deployment capability and yet is poorly designed both for combat against enemy heavy weapons and deploying troops.

They probably didn't have enough fighters that they could dismount the weapons like that, at least, not at Hoth. Remember, fleeing rebel transports only got two X-wings each as a fighter escort, that tells me they were in short supply.

The guns off one X-wing, well mounted and sited, could easily have done a lot more than by escorting one transport. There's a catch, though- the Rebels didn't have time to dismount X-wing cannons for antitank use after the Imperial attack. So all we really know is that they didn't have dedicated tank destroyers for base defense using their limited number of X-wing laser guns in that role, and didn't see the need to build or buy any before the attack.

If we go by the movies and the EU canon 'closest' to the movies (stuff written shortly after, before the proliferation of Rebel assets in the EU started to undermine their perception as the ragtag rebel fleet), X-wings were among the most powerful assets the Rebels had, and they outright stole them. It's no surprise that they didn't have X-wing lasers to spare for things like base defense guns, and had to make do with less powerful weapons.

After all, base defense wasn't their top priority- it was a safe bet that if the Imperials found the base, no amount of ground defense could save the Rebels. At most it could briefly delay an Imperial attack to cover an attempt to break their orbital blockade, which is exactly what happened... and disarming one of your relatively small number of starfighters to improve the antitank firepower of your 'suicidal last ditch' ground defense force isn't necessarily a good plan.

[Crazedwraith]

X-wings have repulsors, but that's not the real issue. The real issue is that this guy expects us to believe that Isard's Revenge makes the rebels look like idiots. I'd prefer to believe differently-that Isard's revenge is subordinate canon and can in fact be wrong about X-wings demolishing AT-ATs with their lasers. If they were so powerful, why not dismount one or a dozen and have an unstoppable anti-tank battery of firepower from concealed positions? Occam's Razor would seem to suggest to me that if X-wings weren't used against the walkers then they wouldn't have been much more effective than the low altitude airspeeders that actually fought the battle.

That's not how canon 'works' if we're going by the rules. You only get to discard things when there's a contradiction not just when you dislike the implications of a work.

And there are plenty of explanations that don't rely on the rebels being idiots;
1)We already know that they were having trouble adapting equipment to Hoth's cold atmosphere. The X-Wings might not have been up to extended operation in the atmosphere
2) X-Wings have real powerful engines. A good burst of speed while attempting a strafing run might have smacked an X-Wing into the top of the shield. A bad way to lose pilots and equipment.
3) They really did need the X-Wings to cover the transport escape. Plus fighters are much more valuble than the speeders. Sending them up against the AT-ATs would have resulted in losses, after all unlike Isard's Revenge they'd have been going up imperial elite. Losing fighters would be bad and would mean they couldn't escort the transports. Meaning they'd lose more of those and thus lose more overall
4) Fuel constraints. We know from the same X-Wing books that sublight and inter-atmosphere operation quickly drains fuel tanks. The X-Wings might not have enough fuel, to fight a delaying action and then make it through the blockade and into hyperspace.

[Sea Skimmer]

On a side note, there's a trivially obvious counter to the towcable trick. Just stop walking. No amount of tying an AT-AT's shoelaces together can make it fall over if it doesn't move. Wait for one of your buddies to cut the cable- this can be done with light antipersonnel fire against the legs, for example.

Or put some helicopter style wire cutters on the legs so you just don't have to worry about it. Perfect job for a light saber if nothing else would cut the cables. Bringing along air defenses, better still.

I think the very idea that the AT-AT is a troop transport itself is a retarded brainbug. It certainly didn't serve that role in the original movie-- when Veers finally blows up the rebel shield generator with his walker's main guns, he doesn't drop his tank to its knees and send out stormtroopers (and really how else are the troops supposed to get out? Climbing ropes?).

You see rebels firing rifles in the direction of the walkers late in the battle; that does kind of imply they had targets like Imperial troops to shoot at in the distance though not with certainty. Dismount is by zip line and repulsorbelts according to various books and they also carry speeder bikes. Having such a giant vehicle with only a few modest sized guns in the head, which don't even take advantage of the full height of the vehicle, seems far more unreasonable then carrying troops. As a transport at least a few of its more glaringly awful problems are reduced, like how on earth it would ever defend itself from attacks to the sides or rear; dismounting troops could accomplish this.

He calls up Vader who is waiting in orbit and tells the Dark Lord that it is safe to land troops. I don't know at what point the EU gave it the secondary role of ferrying soldiers across the battlefield-- the earlier video games like Rogue Squadron and Star Wars Rebellion (aka Supremacy) both treated it as a heavy tank. If I had to guess, though, it would probably be whenever it picked up its current idiotic name-- again, the movie simply referred to them as "Imperial Walkers" which is all you really needed to know.

Well, no he says 'You may start your landing' which may or may not involve additional troops besides Vader. Even if it did involve additional troops that doesn't really tell us anything about the AT-AT since it would still be desirable to land troops directly onto the rebel base ASAP rather then waiting to walk over. Its not like mechanized infantry and airmobile infantry rule each other out in real life. Nor do APCs/IFVs always carry infantry in combat.

[Vehrec]

X-wings have repulsors, but that's not the real issue. The real issue is that this guy expects us to believe that Isard's Revenge makes the rebels look like idiots. I'd prefer to believe differently-that Isard's revenge is subordinate canon and can in fact be wrong about X-wings demolishing AT-ATs with their lasers. If they were so powerful, why not dismount one or a dozen and have an unstoppable anti-tank battery of firepower from concealed positions? Occam's Razor would seem to suggest to me that if X-wings weren't used against the walkers then they wouldn't have been much more effective than the low altitude airspeeders that actually fought the battle.

That's not how canon 'works' if we're going by the rules. You only get to discard things when there's a contradiction not just when you dislike the implications of a work.

And there are plenty of explanations that don't rely on the rebels being idiots;
1)We already know that they were having trouble adapting equipment to Hoth's cold atmosphere. The X-Wings might not have been up to extended operation in the atmosphere.

Counterpoint. X-wings are starfighters and are subjected to much higher temperature extremes in space than hoth could ever produce. Having trouble adapting them for strafing runs when we see them idling outside in the snow rather than in a heated hanger after the main battle is hard to credit.

2) X-Wings have real powerful engines. A good burst of speed while attempting a strafing run might have smacked an X-Wing into the top of the shield. A bad way to lose pilots and equipment.

X-wing repulsors are not going to smack you into the top of the shield-they're roughly the same as an airspeeder in terms of top speed on repulsors.

3) They really did need the X-Wings to cover the transport escape. Plus fighters are much more valuble than the speeders. Sending them up against the AT-ATs would have resulted in losses, after all unlike Isard's Revenge they'd have been going up imperial elite. Losing fighters would be bad and would mean they couldn't escort the transports. Meaning they'd lose more of those and thus lose more overall

If a star destroyer managed to launch half it's fighters, would the X-wing pair be anything more than a speed bump before they tore that transport apart? And since the star destroyers were being knocked out by the Ion cannon, what were the X-wings guarding against that was going to be able to stop the transports without them?

4) Fuel constraints. We know from the same X-Wing books that sublight and inter-atmosphere operation quickly drains fuel tanks. The X-Wings might not have enough fuel, to fight a delaying action and then make it through the blockade and into hyperspace.

The only objection that actually holds water-but why not just land and quickly refuel? We know that they have enough fuel to get from Hoth to Daegoba to Bespin, so why should it effect their fuel tanks so much to make a few straffing runs?

[Purple]

Counterpoint. X-wings are starfighters and are subjected to much higher temperature extremes in space than hoth could ever produce. Having trouble adapting them for strafing runs when we see them idling outside in the snow rather than in a heated hanger after the main battle is hard to credit.

If anything was to cause them problems than it would not be the cold but the snow. Hoth was an ice world with constant snow fall. And that can cause all sorts of problems to engines. Imagine getting an intake full of the stuff for example.

[Wing Commander MAD]

Doesn't Veers directly before or after the scene where he tells Vader to land talk to a stormtrooper officer telling him to prepare his men for ground assualt, who then poceeds to walk back into the main hold? I'd say that's probably a good bet for the origin of the troop transport.

Also, according to Saxton's site the officer bears rank insignia equivalent to an army captain. So it appears the Hoth operation was basically an Imperial army operation with army vehicles and commander, with a company of stormtroopers assigned to the army unit acting as mechanized infantry. Is it even semi rational that you'd have both Veers and the captain in the same vehicle? I get that part of Hoth, according to the EU, was Veers trying to prove the AT-AT design, and thus he probably wouldn't normally be there. In that case I'm presuming the captain would be in charge groundside (at least on the front), and higher ranked officers, such as a colonel, would probably remain in orbit or at the landing zone to coordinate the overall operation, or am I missing something?

[PhilosopherOfSorts]

On the fuel issue, in the X-wing book series its stated that the sublight engines are far less effecient than the hyperdrive. A dogfight burns more fuel than the hyperspace trip to get to the fight and back does. I don't know why this would be, maybe the sublight engines use a different fuel than the hyperdrives?

[YT300000]

Doesn't Veers directly before or after the scene where he tells Vader to land talk to a stormtrooper officer telling him to prepare his men for ground assualt, who then poceeds to walk back into the main hold? I'd say that's probably a good bet for the origin of the troop transport.

Here are the relevant bits from the script:

INTERIOR: IMPERIAL SNOW WALKER -- COCKPIT

Through the cockpit window, Veers and his pilot can see the
Rebel power generators in the distance.
A hologram of Darth Vader appears on a control panel
screen.

VEERS: Yes, Lord Vader. I've reached the main power generator. The
shield will be down in moments. You may start your landing.

....

INTERIOR: IMPERIAL SNOW WALKER -- COCKPIT

General Veers studies various readouts on his control
panel.

VEERS: All troops will debark for ground assault. Prepare to target
the main generator.

....

INTERIOR: IMPERIAL SNOW WALKER - COCKPIT

Inside his walker, General Veers prepares to fire on the
Rebel power generators.

VEERS: Distance to power generators?

PILOT: One-seven, decimal two-eight.

Veers reaches for the electrorangefinder and lines up the
main generator.

VEERS: Target. Maximum fire power.

In the movie, he gives the second command to a snowtrooper in the cockpit. So it does pretty strongly suggest that there are troops aboard.

[StarSword]

Counterpoint. X-wings are starfighters and are subjected to much higher temperature extremes in space than hoth could ever produce. Having trouble adapting them for strafing runs when we see them idling outside in the snow rather than in a heated hanger after the main battle is hard to credit.

If anything was to cause them problems than it would not be the cold but the snow. Hoth was an ice world with constant snow fall. And that can cause all sorts of problems to engines. Imagine getting an intake full of the stuff for example.

It's not so much the snow as it is ice. Again, I ask you to look up "atmospheric icing". I'm oversimplifying, but super-cold temperatures + lots of water vapor in the atmosphere = ice on your wings, in your engines, and on your weapons, all of which can handily ruin your day.