Spensa "Spin" Nightshade
The main character of the story. Spensa wants to be a pilot, but is discriminated against because of her father's alleged cowardice.
- Feminine Women Can Cook: The tomboyish Spensa is the other half of this, as evidenced by this exchange.Rig: And bake me some killer algae biscuits or something.
Spensa: Do you seriously want to eat anything I've baked?
Rig: Now that I think about it, scud no.
- Do I Really Sound Like That?: Spensa eventually hears her typical Flowery Insults from the speakers of M-Bot. When she asks if that's how she sounds, the silence of her fellow pilots is telling.
- Flowery Insult: Spensa is quite fond of these.
- The Napoleon: She is rather short and brash, though her aggression comes from not wanting to be thought a coward instead of her height.
- Psychic Powers: Like her father, she is a cytonic.
- Combat Clarivoyance: She can eavesdrop on the cytonic command links the Krell pilots use to control their drone interceptors, knowing what the drones will do before they even do it.
- Psychic Starship Pilot: Capable of FTL teleportation, and with the right setup could bring a whole ship along with her.
Rodge "Rig" McCaffrey
Spensa's longtime best friend, who shares her dream of becoming a pilot. He later drops out of flight school and becomes an engineer.
- The Engineer: He's surprised to find that he has a talent for this, and far prefers it to being a pilot.
An artificial intelligence residing in a centuries-old fighter more advanced than any Defiant ship, awakened by Spensa when she finds a centuries-old fighter.
- Bunny-Ears Lawyer: M-Bot takes an obsessive interest in analyzing mushroom samples due to orders left by his former pilot. Though he could edit that directive out of his program, he chooses not to do so, since he thinks of it as his hobby.
- Cloud Cuckoo Lander: Rig suspects it's due to damage.Rig: Can you imagine anyone intentionally programming him to act like that?
- Loophole Abuse: He cannot deliberately violate his pilot's orders, even centuries after his pilot died. But he was able to write a routine that could sneak in when his main AI wasn't looking, and change who his pilot is.
- Lost Technology: He is the Lost Technology.
- Normal Fish in a Tiny Pond: He's implied to have been a fairly normal (if slightly high-end) design for pre-war humanity, but compared to the stolen Krell tech and the centuries-old Defiant ships, he is practically god-like in his capabilities.
- Personality Chip: Does this to himself by writing subroutines that do things like help him express outrage, and teach him fear of death.
Jorgen "Jerkface" Weight
The heir to a family of elite politicians, and the appointed leader of Skyward Flight. Jorgen does not always have the best people skills but he genuinely wants to become a good leader and help others.
- Royal Brat: Feels entitled to respect he hasn't earned and can be petty when he's jealous. He gets better as he learns the reality of war.
- Spoiled Brat: Subverted. Jorgen seems like an expy of the Draco Malfoy-esque upper-class bully, what with his pompous attitude, family connections, and wealth. This isn't entirely true: While pompous, Jorgen is very skilled at use of flight simulators, and he's not happy with his lack of choice in being anything but this.
A flight instructor within the DDF, and previously wing-mate to Spensa's father. Cobb sticks his neck out to admit Spensa into his class.
- Cultural Rebel: Cobb is a senior DDF soldier, and one of the valorised "First Citizens" who held the line at the Battle of Alta. He has nothing but contempt for the modern DDF's martyrdom culture. He's the only instructor who tells his students that their lives are more valuable than a slim chance of saving their ship.
- Easily Forgiven: Spensa holds a grudge against the entire DDF for dishonouring her father, but aside from some initial surprise never resents Cobb for being the one who personally killed him.
- Screw the Rules, I Have Connections!: Cob isn't above using his status as First Citizen to bypass the chain of command or break DDF rules. In an unusually positive spin on the trope, he's only ever seen doing this to help his students, particularly Spensa.
- Shell-Shocked Veteran: Cob seems to suffer from some sort of PTSD, severe enough to prevent him from flying a starfighter despite his years of experience and the DDF's pilot shortage. He developed this after being forced to shoot down Spensa's father in the Battle of Alta.
Admiral Judy "Ironside" Ivans
The commanding officer of the DDF, who bears a strong (even by the standards of Defiant culture) grudge against Spensa, resorting to every possible tactic, no matter how petty, to keep her out of flight school.
There's a better reason for this than Spensa thinks.
- Closest Thing We Got: Privately, she doesn't think she's qualified to lead the DDF. The only time someone else expresses that opinion, she points out that anyone more qualified than her died years ago.
- Heroic Sacrifice: Invoked in the finale. Ironsides gives orders to shoot down the Krell bomber immediately to protect the lower caverns, knowing full well the resulting explosion will kill her. Spensa ignores her, and pulls off a much more risky plan to save everyone.
- The Chains of Commanding: Suffers greatly, to the point that she says she wouldn't wish her job on anyone.
- The Dead Have Names: No matter how busy she gets, Ironsides makes a point of reading the casualty lists and personally composing letters to the families of the dead. She does her best to memorise the name of every fallen pilot, but she's been unable to. There are too many.