Automail

Automail is a type of prosthetic limb present in the series Fullmetal Alchemist that is used by various characters in the series as a replacement for lost or damaged body parts.

Anatomy of Automail
Automail is made from metal and linked directly to the nerves of the body. Automail can be used on both humans and animals. In certain situations, automail can be designed to replace huge portions of the body. Also present in the series are normal prosthetics, not linked to the body's nervous system. Many amputees choose to use these over automail, despite the numerous advantages automail has. This is because of the intense pain experienced during the surgery to attach automail to the body as well as when the automail is first connected, when all the nerves first connect.

Types of Automail
Well-made automail allows a range of movement and strength as good as or better than the original limb it replaces. It is never directly stated how automail is powered, but it is known that the technology grew from the science of alchemy. When the metal coverings are removed, a type of fiber is seen.

People with Automail
Edward Elric, the main character of the series, has two sets of automail, one in place of his right arm, and one in place of his left leg. The artificial arm and leg were given to him to replace the limbs Ed lost during his ill-fated attempt at human transmutation. Edward's automail functions well enough to allow him to engage in martial arts practice, acrobatics, and fighting. Edward can also transmute his automail arm to add a wrist-mounted blade to it, or place spikes on his knuckles. The mechanic that created his automail was Pinako Rockbell, with help from her granddaughter Winry Rockbell. After a battle with Scar, Ed's arm was destroyed and had to be rebuilt. A new, lighter design was adopted, after concerns that the previous model was hampering Ed's speed and possibly stunting his growth. While it was a success in this regard, it sacrificed some of its durability in exchange, and it remained incomplete until after the 5th Laboratory incident. Winry realized that she forgot a bolt in the arm soon after Ed entered the Lab. Ed however didn't realize this and thought it was his fault the automail broke. In truth, it was a combination of both. This model was created and maintained by Winry herself. In the Fullmetal Alchemist movie, Ed has lost both his original limbs and the original automail that replaced them, but not the fixings attached to his body. He has replaced them with what appear to be normal prosthetics built on Earth technology, but the skin-like covering on his arm can be removed, revealing a small motor-driven apparatus which increases the strength and maneuverability of his arm. At the end of the film, Winry replaces it with Rockbell automail, which she had the foresight to lengthen to account for Ed's two years of growth. In manga chapters 69-70, under military orders, Winry was sent to Briggs with reason "to upgrade Edward Elric's automail", which is incapable of functioning properly under Briggs' freezing temperature. However, besides that, she also minimizes the weight of the automail, much to Ed's joy, as his initial automail had been very heavy, and his balance perception adjusted to compensate. Using subsequent lighter automail meant adjusting to the new weight of his body and limbs, a long process of trial and error, which could prove fatal if he entered combat with unfamiliar automail. Working with heavy automail again would have meant becoming re-accustomed to its weight, as well as it having an impact on his growth. Unfortunately, the reduced weight also means reduced durability, but as Winry reassures him, "The important parts are reinforced."

Lieutenant Colonel Frank Archer is an intelligence officer in the military who uses automail. After the destruction of the left half of his body at Lior he was heavily modified with automail, including the left side of his face. This may suggest that automail is capable of replacing even vital organs. In addition, his arm was equipped with a folding auto-cannon weapon, while his mouth contained a machine gun in the place of a tongue. As a result, he doesn't open his mouth to talk and so it can be inferred that a vocoder was implanted somewhere in him. He would later use both weapons to devastating effect. Actually, due to his extensive Automail, he can be considered a cyborg, rather than an amputee (all other Automail users are amputees). Frank Archer is exclusive to the anime.