Narrative:

ATC issued a descent to cross hilltop at 13000 ft. I diverted my attention to review the STAR. While my attention was on the review of the STAR, the aircraft MCP put the aircraft into an 'altitude hold' mode. After the review of the STAR and completion of a checklist, I noticed the altitude hold. I started a descent and the PNF advised ATC we might not make the crossing altitude. ATC acknowledged, gave us an unrestr descent and clearance for a visual approach.

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Original NASA ASRS Text

Title: B757 FLT CREW FAILS TO MAKE AN ALT XING RESTR AT HILLTOP, CA.

Narrative: ATC ISSUED A DSCNT TO CROSS HILLTOP AT 13000 FT. I DIVERTED MY ATTN TO REVIEW THE STAR. WHILE MY ATTN WAS ON THE REVIEW OF THE STAR, THE ACFT MCP PUT THE ACFT INTO AN 'ALT HOLD' MODE. AFTER THE REVIEW OF THE STAR AND COMPLETION OF A CHKLIST, I NOTICED THE ALT HOLD. I STARTED A DSCNT AND THE PNF ADVISED ATC WE MIGHT NOT MAKE THE XING ALT. ATC ACKNOWLEDGED, GAVE US AN UNRESTR DSCNT AND CLRNC FOR A VISUAL APCH.

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.