AT-ATs on Hoth - How?

Drop ships

 

Same way the troopers got there - off-screen.

 

The AT-STs grew into AT-ATs WITH EXCELLERATED GROWTH LIKE THE CLONES FROM AOTC.

 

When Lucas first created Star Wars his vision for it would be the antithesis of Science fiction like Star Trek. His creation was space adventure and the hows and the whys were irrelevant. It just "is".

 

For a logical explanation, drop ships or landing ships would easily explain it away, similar to what our military uses to transport tanks and the like all over the world, just like what The Spruce Goose was supposed to do that was built by Howard Hughes, but we use those designs currently (just not wood lol).

 

They hid in the Wampa cave until the perfect time to strike!

 

Something like this:

 

Here's some TESB concept art showing an AT-AT being deployed on Hoth by an Acclamator Class Star Destroyer transport.

The same transport could deploy what we now call the Juggernaut, or Turbo Tank, which was not used in TESB. The ten-wheeled armored vehicle eventually made it to the big screen in ROTS.



Here's the Wookipedia entry for the transport-

http://starwars.wikia.com/wiki/Acclamator-class_transport_drop_ship

 

Or like that \m/

 

Do you know why it didn't make it into the film in the end?

 

I know the Juggernaut was a design that Joe Johnston sketched out, and that it was decided that the AT-AT would be used in TESB instead of the Juggernaut, but I don't know any more details beyond that.

 

Considering the landing method of the probe droid, I believe that the ventral bulb of a Star Destroyer is an AT-AT lander platform. Simply send a bomb into the center of resistance (will create a nice crater) and then "nest" your platform in there to have AT-ATs spread out into all directions.
The speed of such procedure should practically make it impossible for planetary defences to shoot down the lander.

Since the nuEU (e.g. Rebels, Star Wars Battlefront and Episode VII) reveals that Star Destroyers can fly in atmospheres, these platforms could be simply picked up / be reinserted after each AT-AT mission is finished.

 

That's a very cool idea, and the Fantasy Flight Game Star Wars: Armada further confirms that Star Destroyers can indeed operate in a planet's atmosphere.

However, I don't think the ventral bulb is used in the way you describe because all of the schematics and cross section drawings I have access to, as well as a couple of large scale resin SD models I've built, identify that part as the "Solar Ionization Reactor"-



It's a large sphere at the heart of the ship. You can see the top side of it in this cross section outlined in red-


I'd love to see your platform idea incorporated into some new or future version of the SD.

 

Well, when I returned from the Marin County Fair Lucasfilm Exhibit in 1988 with plenty of pictures of the Devastator and Avenger (VFX models) one of my friends made painstakingly, accurate side view drawings. One of the first things he told and showed me - assuming it's a sphere - was that the curvature of the ventral bulb then would be the "tip" of a sphere that extends all the way and above the upper super structure!

In addition we see objects on the ventral bulb that look like clamps, but since a sphere couldn't fit through the opening, it rather looks as if the ventral bulb could be a kind of cover (but nevertheless with a reactor or a reactor assembly above on the inside, pending on further "suggestions" by Rebels and TFA - what I've see thus far seems to suggest large open spaces inside).

Alternately the reactor isn't a sphere but closer to a saucer, but then it would be at a rather exposed and possibly vulnerable location (but an AT-AT lander platform ahead of the actual reactor would constitute some kind of protection or "armor plating").

Now that Star Destroyers can enter atmospheres and don't need transport barges any more, downloading is still an issue, given the unique shape. The one lowest and closest to the ground remains the ventral bulb, hence the idea.

P.S. For the OT Cross-Sections book (the image you provided) Dr. David West Reynolds chose the lesser seen top side of the Devastator with the "big" lateral guns (supposedly Lucas didn't like the guns, hence the majority of shots in the films from below). Assuming these reach their optimal broadside firing position by slightly tilting the ship would then also expose the ventral bulb much better for any opponent...

 

To me, and this is from a Venator-class destroyer, it looks like the spherical looking bulge on the bottom of this version fires an extremely powerful blue super laser. Just after the clip starts you can see and hear it firing from the destroyer on the top left.

 

Agreed with @Crusifix
http://starwars.wikia.com/wiki/Y-85_Titan_dropship

 

It should be noted too that Vader's attack plan was to use AIRCRAFT then bomb Echo Base to bits, then deploy snow troops & regular ground-mech infantry units to take over the rebel base.
The Imperial admiral or fleet CiC screwed up & brought the Imperial fleet too close to the planet(this was due to the large asteroids/belts) that surrounded Hoth.
The ships and bombers might have sustained serious damage but Vader correctly guessed the Rebel Ion Cannon & powerful shields could stave off a direct ground assault or slow down the AT ATs, Scout Walkers.

The Rebels were constantly moving and hiding. They picked Hoth as a temporary base to regroup & plot their next major objective.
Hoth was not a great choice but it was hard to reach & Imperial troops could not sweep in & wipe them out.
That's partly why they built the huge Ion cannon to zap Star Destroyers or large ships to cover the escapes.
This action is what's in TESB. They knew they couldn't fight off waves of huge AT ATs or troops but they could flee.

 

^^ Could you please elaborate how you arrived at such a precise conclusion?

RIEEKAN With all the meteor activity in this
system, it's going to be difficult
to spot approaching ships.

CONTROLLER General, there's a fleet of Star
Destroyers coming out of hyperspace
in sector four.

VEERS My lord, the fleet has moves out
of light-speed. Com-Scan has
detected an energy field protecting
an area around the sixth planet of
the Hoth system. The field is
strong enough to deflect any
bombardment.

VADER (angrily)
The Rebels are alerted to our
presence. Admiral Ozzel came out
of light-speed too close to the
system.

Apparently Vader's strategy would have been to leave hyperspace outside the Rebels' scaninng range and then have the fleet perform silent running to make a stealth approach (difficult to tell Star Destroyer from asteroid apart) and then have the missile launchers target and destroy the Hoth power generators (missiles would have probably been mistaken for meteorites until it was too late to tell the difference).

Nothing in the dialogue indicates the use of TIE twin-pod bombers. I'd dare to say that these would have been too slow and detected in advance, therefore the "bombardment" probably referred to bombardment from orbit.