航后机组报告，HF在飞行中质量不好，可是返回地面再检查一切正常，判断可能是什么原因

THE DESCRIPTION OF THE WINDOW DEFECTS IS GIVEN IN THE:

COMPARED TO THE A319/A320 AND A321, THE A318 VERTICAL STABILIZER IS:

THE ESCAPE SLIDE (OR SLIDE/RAFT) CONTROL MECHANISM:

IF A PASSENGER DOOR IS CLOSED AND LOCKED:

DURING NORMAL OPENING OF A PASSENGER DOOR, ON THE DOOR PAGE OF THE ECAM:

A RED FLASHING LIGHT ON THE PASSENGER DOOR INDICATES THAT:

A WHITE "SLIDE ARMED" LIGHT AT THE PASSENGER DOOR INDICATES:

THE VARIABLE STATOR VANES AND VARIABLE BLEED VALVES ARE:

A NACELLE TEMPERATURE SENSOR MONITORS THE:

THE ELECTRONIC CONTROL UNIT (ECU) IS LOCATED: