Narrative:

On climb/cruise to flight level, ZJX cleared us to climb from FL280 to FL290. New altitude was set in window and both of us acknowledged with point. A couple of mins later (2), the controller called again to give clearance to climb to FL290. We had failed to initiate the climb after setting it in the window. Climb was started and no conflicts were involved.

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Original NASA ASRS Text

Title: BOTH B737 CREW MEMBERS ACKNOWLEDGED A CLB CLRNC. NEITHER INITIATE THE CLB.

Narrative: ON CLB/CRUISE TO FLT LEVEL, ZJX CLRED US TO CLB FROM FL280 TO FL290. NEW ALT WAS SET IN WINDOW AND BOTH OF US ACKNOWLEDGED WITH POINT. A COUPLE OF MINS LATER (2), THE CTLR CALLED AGAIN TO GIVE CLRNC TO CLB TO FL290. WE HAD FAILED TO INITIATE THE CLB AFTER SETTING IT IN THE WINDOW. CLB WAS STARTED AND NO CONFLICTS WERE INVOLVED.

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.