Flight Crew Last 90 Days 240; Flight Crew Total 15500; Flight Crew Type 4000
Confusion; Situational Awareness; Human-Machine Interface; Distraction
Deviation - Altitude Excursion From Assigned Altitude; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Became Reoriented; Flight Crew Returned To Clearance; Flight Crew Took Evasive Action
Procedure; Aircraft; Human Factors
As the aircraft was leveling at 370 with the autopilot and autothrottle engaged; the Flight Attendant brought our breakfast to the cockpit. The Captain was monitoring the aircraft while I got out of my seat to open the door and retrieve the meals. After sitting back down in my seat; I glanced down at the airspeed and saw it rapidly decaying to green dot. I then looked at the airspeed window on the display management panel and noted that a speed of 205 KTS was displayed in the speed window. I made a callout to the Captain of 'airspeed.' We did not have enough thrust to stop the airspeed from deteriorating; so the Captain disconnected the autopilot and lowered the nose to accelerate. As he lowered the nose; he began a gradual descent. He then instructed me to call ATC and ask for a block altitude. As he was asking me to call ATC; Center called us and asked us our altitude and we requested a block altitude of 330-370. The request for the block altitude was granted. I was quite busy monitoring the airspeed and radio; but I believe we descended 500-600 FT to get the airspeed back and start climbing. We climbed back up to 370 without any further incident.
The First Officer reported that the Captain entered the performance data during preflight and when scrolling through the Performance Preflight pages somehow skipped over the Climb Performance page and in the following page; Cruise Performance; entered 205 KTS. As a result; when the aircraft leveled at FL370; just as the reporter was retrieving crew meals; the aircraft slowed toward 205 KTS and the Captain did not immediately see the decrease. As a result; the heavy A320 could not accelerate by thrust alone and so an altitude decrease was necessary.
An A320 Captain entered the preflight performance data and apparently skipped the Climb Performance page and entered 205 KTS as the Cruise Performance airspeed parameter which resulted in a speed loss during transition from climb to cruise.