Because they're cultists. Who flies a ship with balloons? Why are you expecting logic to apply here. [Okay, so maybe there was some extra aggravation in her tone there, but they were dealing with cultists and that was enough to put her in a bad mood.]

Let's just go find them before they decide blowing up the ship sounds like a great idea while we're still on it.

[She turns to the left, keeping close to the railing and watching for any sign of movement. It seems quiet, but she's not taking chances.]