Narrative:

I was the captain on aircraft X parked at the gate. After the agent closed the door; the number 1 flight attendant (flight attendant) came to the cockpit and said she couldn't arm the 1R door. This we confirmed this on the door ECAM page. I went back to look at door and confirmed it wouldn't arm. I disarmed door and cycled it. The arming lever would not arm. I disarmed the door again and confirmed the arm light was not lit and the green disarmed indicator showed disarmed; not armed. Both flight attendant's in galley confirmed this. I opened the door slightly and the slide deployed. My first officer (first officer) confirmed that cockpit indicated not armed at deployment. No one was injured.

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Original NASA ASRS Text

Title: B777 Captain reported a cabin door arming issue led to an inadvertent slide deployment.

Narrative: I was the Captain on Aircraft X parked at the gate. After the agent closed the door; the number 1 FA (Flight Attendant) came to the cockpit and said she couldn't arm the 1R door. This we confirmed this on the door ECAM page. I went back to look at door and confirmed it wouldn't arm. I disarmed door and cycled it. The arming lever would not arm. I disarmed the door again and confirmed the arm light was not lit and the green disarmed indicator showed disarmed; not armed. Both FA's in galley confirmed this. I opened the door slightly and the slide deployed. My FO (First Officer) confirmed that cockpit indicated not armed at deployment. No one was injured.

Data retrieved from NASA's ASRS site 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.