Narrative:

I was flying and the captain was making a PA announcement. I received a descent from nyc on (135.75) to 10000 ft. I thought this was odd since the STAR has 'mazie' at 11000 ft. I believe I read back 10000 ft. Later nyc informed us the altitude was 11000 ft, this was at 10400 ft. We corrected back to 11000 ft without incident. The controller reported no conflicts. I believe the 10000 ft PA announcement to passenger and flight attendants is unsafe and usually occurs when we are busy. A switch with light as a 'sterile cockpit' signal would be safer.

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Original NASA ASRS Text

Title: MISTOOK CLRNC TO 11000 FT AS 10000 FT. ATC INTERVENED WHEN ACFT WAS 600 FT BELOW 11000 FT. CTLR RPTED NO CONFLICTS.

Narrative: I WAS FLYING AND THE CAPT WAS MAKING A PA ANNOUNCEMENT. I RECEIVED A DSCNT FROM NYC ON (135.75) TO 10000 FT. I THOUGHT THIS WAS ODD SINCE THE STAR HAS 'MAZIE' AT 11000 FT. I BELIEVE I READ BACK 10000 FT. LATER NYC INFORMED US THE ALT WAS 11000 FT, THIS WAS AT 10400 FT. WE CORRECTED BACK TO 11000 FT WITHOUT INCIDENT. THE CTLR RPTED NO CONFLICTS. I BELIEVE THE 10000 FT PA ANNOUNCEMENT TO PAX AND FLT ATTENDANTS IS UNSAFE AND USUALLY OCCURS WHEN WE ARE BUSY. A SWITCH WITH LIGHT AS A 'STERILE COCKPIT' SIGNAL WOULD BE SAFER.

Data retrieved from NASA's ASRS site as of July 2007 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.