Narrative:

ATC had issued a crossing restr which I acknowledged and had read back. The PF acknowledged and dialed in the appropriate altitude in the MCP. Unfortunately I did not confirm the captain was beginning his descent as I turned my attention to prepare for the next flight trying to stay well ahead of the aircraft. Unfortunately, I felt I turned my attention too far ahead.

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Original NASA ASRS Text

Title: AN ACR FLC FLYING B737 FAILS TO MEET ALT XING RESTR NEAR PHL.

Narrative: ATC HAD ISSUED A XING RESTR WHICH I ACKNOWLEDGED AND HAD READ BACK. THE PF ACKNOWLEDGED AND DIALED IN THE APPROPRIATE ALT IN THE MCP. UNFORTUNATELY I DID NOT CONFIRM THE CAPT WAS BEGINNING HIS DSCNT AS I TURNED MY ATTN TO PREPARE FOR THE NEXT FLT TRYING TO STAY WELL AHEAD OF THE ACFT. UNFORTUNATELY, I FELT I TURNED MY ATTN TOO FAR AHEAD.

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.