Narrative:

Upon reaching the aircraft we both began our preflight of aircraft. I personally reviewed the logbook and noted that the aircraft had just come out of a weekly inspection. I also noted all maintenance items were signed off as complete. My first officer also reviewed the logbook and we discussed that an oil service was done to both engines. We had a normal taxi and completed all checklists before departure. The takeoff was uneventful with gusty winds and we climbed to 5;000 ft. At that point; the lead flight attendant called us and informed us that a passenger had informed her that 'a panel had come off the right wing.' I had the first officer tell her to get verification from the flight attendants that they did see a problem. Moments later; the lead flight attendant called back and verified that 'wires and pipes' were exposed on the right wing. [The first officer] and I briefly discussed the situation and agreed that we should return to the airport for an inspection. [First officer] notified ATC of our intentions and shortly afterward I declared an emergency to ATC. [First officer] was very busy running landing data; contacting dispatch; and running checklists while I was flying the aircraft and talking to ATC. I also notified ATC that they should inspect [the runway] for possible debris. We set up for the [the approach] and discussed the overweight landing. The landing was uneventful. We ran the after landing checklist and secured the number 2 engine. I then contacted the fire commander and requested that they inspect the aircraft for visible damage. The fire commander called us back and confirmed that the number 2 engine was damaged he also recommended that the aircraft be towed back to the gate.after getting this information we secured the number one engine as well. It took some time to arrange a tow back to the gate. We kept the passengers informed during the entire event. Upon arrival at the gate; we ran the parking checklist and I made entries into the logbook for the number 2 engine cowl departing the aircraft in flight and for the overweight landing. My first officer did an excellent job during the entire event; his work load was very heavy in a short amount of time and he performed flawlessly. In addition; our cabin crew did an excellent job with communication and keeping the passengers calm and quickly preparing for landing.

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Original NASA ASRS Text

Title: A319 flight crew reported they were notified by a Flight Attendant that a passenger had pointed out missing skin in the area of Number 2 Engine. Flight declared an emergency and returned to departure airport; where postflight inspection revealed the Number 2 Engine cowl had departed the aircraft in flight.

Narrative: Upon reaching the aircraft we both began our preflight of aircraft. I personally reviewed the logbook and noted that the aircraft had just come out of a weekly inspection. I also noted all maintenance items were signed off as complete. My First Officer also reviewed the logbook and we discussed that an oil service was done to both engines. We had a normal taxi and completed all checklists before departure. The takeoff was uneventful with gusty winds and we climbed to 5;000 FT. At that point; the Lead Flight Attendant called us and informed us that a passenger had informed her that 'a panel had come off the right wing.' I had the First Officer tell her to get verification from the flight attendants that they did see a problem. Moments later; the Lead Flight Attendant called back and verified that 'wires and pipes' were exposed on the right wing. [The First Officer] and I briefly discussed the situation and agreed that we should return to the airport for an inspection. [First Officer] notified ATC of our intentions and shortly afterward I declared an emergency to ATC. [First Officer] was very busy running landing data; contacting Dispatch; and running checklists while I was flying the aircraft and talking to ATC. I also notified ATC that they should inspect [the runway] for possible debris. We set up for the [the approach] and discussed the overweight landing. The landing was uneventful. We ran the after landing checklist and secured the Number 2 Engine. I then contacted the fire commander and requested that they inspect the aircraft for visible damage. The Fire Commander called us back and confirmed that the Number 2 Engine was damaged he also recommended that the aircraft be towed back to the gate.After getting this information we secured the number one engine as well. It took some time to arrange a tow back to the gate. We kept the passengers informed during the entire event. Upon arrival at the gate; we ran the parking checklist and I made entries into the logbook for the Number 2 Engine cowl departing the aircraft in flight and for the overweight landing. My First Officer did an excellent job during the entire event; his work load was very heavy in a short amount of time and he performed flawlessly. In addition; our cabin crew did an excellent job with communication and keeping the passengers calm and quickly preparing for landing.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.