Flight Path in Chalk

I kicked a stubby piece of white chalk out from under the tool rack with the tip of my foot. Starship captains probably have glowing holo-maps, but interns... well, we make do. Leaning my whole weight down, I shoved the chalk along the dark cedar floorboards, leaving a thick powdery line that hooked into a clumsy arrow pointing toward the sliding door. It made a loud, gritty screech that made my visor vibrate. I clicked my harness strap against my chin and mumbled, 'Uh, Rob... I plotted the emergency evacuation vector on deck, in case you... well, in case you need to find me. Do you copy?' Only quiet fuzz answered, but the white chalk mark stayed totally clear.