Narrative:

Center gave us clearance to cross djb 180 degree right at 30 DME at FL310. I (PNF) read back clearance. Captain (PF) entered clearance into FMS, but it would not accept data entry. So he tried again, but still no acceptance. So I tried it, but still no acceptance. By now about 1 min had gone by. Controller asked us if we were going to make crossing restriction. I said, 'no,' we would be unable to make. The PF had not even left the previous altitude (FL390). We immediately began descending.

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Original NASA ASRS Text

Title: ADVTECH ACR LGT FAILS TO MEET CROSSING RESTRICTION IN DESCENT.

Narrative: CTR GAVE US CLRNC TO CROSS DJB 180 DEG R AT 30 DME AT FL310. I (PNF) READ BACK CLRNC. CAPT (PF) ENTERED CLRNC INTO FMS, BUT IT WOULD NOT ACCEPT DATA ENTRY. SO HE TRIED AGAIN, BUT STILL NO ACCEPTANCE. SO I TRIED IT, BUT STILL NO ACCEPTANCE. BY NOW ABOUT 1 MIN HAD GONE BY. CTLR ASKED US IF WE WERE GOING TO MAKE XING RESTRICTION. I SAID, 'NO,' WE WOULD BE UNABLE TO MAKE. THE PF HAD NOT EVEN LEFT THE PREVIOUS ALT (FL390). WE IMMEDIATELY BEGAN DSNDING.

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.