The Design For Star Wars' AT-ST 'Chicken Walker' Was Cobbled Together From Scrap
The Battle of Hoth in "The Empire Strikes Back" consists mostly of four-legged AT-AT walkers bearing down on a Rebel base as Luke Skywalker and other snowspeeder pilots fly out to meet them. However, there's one shot where the AT-AT's two-legged cousin, the AT-ST, or chicken walker, ambles past the camera, looking a little out of place in retrospect. The AT-ST would take on a more prominent role as a target of Ewok aggression in "Return of the Jedi," but it was originally designed by Joe Johnston late in the VFX process for "The Empire Strikes Back."
Johnston went on to become a filmmaker in his own right, directing "The Rocketeer" and "Captain America: The First Avenger," among other movies, but he started out as a designer and visual effects artist on the original "Star Wars" trilogy. A few years ago, we toured the "Star Wars: Identities" exhibition, where you could see some of Johnston's concept sketches for things like the Millennium Falcon cockpit and Death Star surface on display. For the AT-ST walker, however, Johnston skipped the sketches and went straight to the model-making process. Speaking to StarWars.com in 2020, he said of the AT-ST:
"It's one of the models that was designed through kit bashing. I didn't do any drawings of it before I had a three-dimensional model of it. I just used model kits and planes and there was a model by — I forget the company name, it was a bulldozer. It had a lot of great parts. I basically was making the prototype and making it in three-dimensional form instead of doing sketches first. I finished the model, I showed George [Lucas], he liked the design a lot. He said, 'That's great, but we don't have any time. ... We'll use it in the sequel.'"
Stray chicken
Most of Joe Johnston's work on "Star Wars" was done behind the scenes, but in the same way that he cobbled the AT-ST together from model kit scraps, the movies themselves were often a makeshift affair where a lot of pioneering was done. While the AT-ST came together late in the game and "Star Wars" creator George Lucas decided to save it for the sequel (then called "Revenge of the Jedi," though it would be softened to "Return of the Jedi"), stop-motion animator Phil Tippet had an idea for how they could get some of Johnston's work into the actual movie. Explaining how that stray shot of the AT-ST in "The Empire Strikes Back" originated, Johnston said:
"Phil Tippett came in and said, 'What if I took the model?' The three-dimensional prototype, which was just a static model. All it did was just sort of stand there. He said, 'What if I took the model, took it apart, and attached the pieces to a stop motion armature? We can build an armature super-fast because it was just basically these aluminum arms.' He said, 'I think we'll have time to get it into a few shots.' So he did that. He basically destroyed the model but then reattached all the pieces to this armature. He was able to get it into one shot in the background, where it's just sort of cruising through."
Johnston also helped design Yoda, Boba Fett, and the AT-ATs (per Yahoo), so he still saw plenty of his work onscreen in "The Empire Strikes Back." And in the same way that the AT-ST model cameoed in that film, the AT-AT would later make a short appearance in "Return of the Jedi" when Luke Skywalker turns himself into Darth Vader on the forest moon of Endor.