Narrative:

First officer (first officer) performed walk around on aircraft and found all inspection panels visually secure. Afterward; entered in logbook and safety inspection form all complete. Ramp agent on ground indicated aircraft all secure for pushback. Proceeded to de-icing. No indication from de-icing crew of any abnormalities or panels not secured. Flew to ZZZ1 uneventfully (no indication of any abnormalities). Once parked at ZZZ1; gate was notified by ground crew that the panel was missing and another open on number one engine nacelle. My first officer and I proceeded to investigate on ramp and found oil inspection access panel totally torn off from hinge and the air starter valve access panel open with no damage. My first officer and I continued to inspect for any damage from departing panel. We noticed possible scrape on left rear empennage; leading toward APU access panel and also noticed one of four latches on APU panel unlatched; rest (of them) secure. Also noticed an attachment screw to APU panel was popped out; unsecured. Did not see any damage to control surfaces or other parts of aircraft visually. In my opinion oil access panel may have popped out in flight from excess pressure within the nacelle itself. Otherwise; how would oil panel and air starter panel both open in flight? But all indications in the cockpit were normal throughout all ground and flight operations.

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Original NASA ASRS Text

Title: Upon flight arrival at the gate; a Captain and First Officer are notified by Ground Crew that an Oil service access panel was missing on the # 1 engine cowling of their EMB-145; and the Air Starter access panel was hanging down. The Oil access panel; it's hinge and part of the engine cowling skin had been torn away.

Narrative: First Officer (FO) performed Walk around on aircraft and found all Inspection panels visually secure. Afterward; entered in Logbook and safety Inspection form all complete. Ramp agent on ground indicated aircraft all secure for pushback. Proceeded to de-icing. No indication from de-icing Crew of any abnormalities or panels not secured. Flew to ZZZ1 uneventfully (no indication of any abnormalities). Once parked at ZZZ1; gate was notified by Ground crew that the panel was missing and another open on Number One engine nacelle. My FO and I proceeded to investigate on ramp and found Oil inspection access panel totally torn off from hinge and the Air Starter valve access panel open with no damage. My FO and I continued to inspect for any damage from departing panel. We noticed possible scrape on left rear Empennage; leading toward APU access panel and also noticed one of four latches on APU panel unlatched; rest (of them) secure. Also noticed an attachment screw to APU panel was popped out; unsecured. Did not see any damage to Control surfaces or other parts of aircraft visually. In my opinion Oil access panel may have popped out in flight from excess pressure within the nacelle itself. Otherwise; how would Oil panel and Air Starter panel both open in flight? But all indications in the Cockpit were normal throughout all ground and flight operations.

Data retrieved from NASA's ASRS site as of April 2012 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.