Drones
When The Pilot returns to duty she is told that she will be piloting a drone, not in the cockpit of a fighter jet. This is a symbol that she has been castrated as she believes she is being punished for having a child, being a woman.
Counseling
When The Pilot begins having issues her husband asks her to go to counseling. This, to her, is a symbol of weakness and is pathetic for someone who is in war every day. It is not the way it is supposed to be done.
Sam
The Pilot comes home to kiss Sam goodnight when she sees her daughter is grey. She turns the lights on to see that she is not grey, but alive. This is a symbol that The Pilot's life in the war during the day is bleeding into her reality at home.
Grey
The screen being grey at work is a symbol that war only sees things in a gray zone, there is no color only objectives and targets.
Flight Suit
At the beginning of the play, we see The Pilot in her flight suit. It becomes a symbol that she has made a kill during the day when she wears it home to her husband.