Instructing Heavyarms to draw the line back up with one hand, Trowa used his other to set the security parameters to the default normal-- allow no strangers to approach within ten feet, fifteen being a warning shot, which seems reasonable for the area. There's not that much room to maneuver. Allow other pilots displaying non-hostile tendencies within the perimeter. Close the cockpit once he's on the ground and retract the zipline.
That done, he slid down to the ground himself and cautiously followed Jiraiya up the steps and into the little cabana-looking thing with his hand prudently on his weapon. Going from a bright place into a dark one meant his eyes would need to adjust.