public void describeStatus(Description d) {
    if (pilot != null && pilot.mind.rootBehaviour() != null) {
      pilot.mind.rootBehaviour().describeBehaviour(d) ;
    }
    else if (motion.target() != null) {
      if (motion.target() == aboard()) d.append("Aboard ") ;
      else d.append("Heading for ") ;
      d.append(motion.target()) ;
    }
    else {
      d.append("Idling") ;
    }
  }