Narrative:

On flight from lax to jfk, we were cruising at FL370. We were assigned to cross harty intersection on the lendy 4 arrival to jfk at FL230. The aircraft was on autoplt and in VNAV. The expected clearance altitudes were previously programmed into the FMC. Upon receiving the crossing restr at harty, the captain entered FL230 in the FMC cruise page and executed the instruction. The MCP altitude was set to FL230. I notified center we were leaving FL370 to FL230. At this time I resumed my PNF duties of updating the ATIS and making a final PA to the passenger. When I finished, I noted the aircraft was still at FL370 and only 10 mi or so to harty. I notified the captain, who started an immediate descent in flight level change mode. I then notified ATC that we would not make the crossing restr at harty, as we did have about an 80 KT tailwind at the time. We crossed harty some 1500-2000 ft high. To my knowledge, no loss of separation occurred. The point of this report is that the automation in modern airliners is great, and in my experience works correctly 99.9% of the time. This success rate lulls us into complacency, believing the system will always do what we have programmed it to do. When using the automation, however, we should be extra vigilant to ensure the automation does do what we want it to do! I still don't know why the aircraft remained at FL370 when the new cruise altitude was set to FL230. The failure here, however, was that we failed to notice immediately that the system was not doing what we wanted it to do.

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Original NASA ASRS Text

Title: A B767-300 FLT FAILS TO MAKE A XING RESTR WHEN THE CREW FAILS TO NOTE THE FMS WAS NOT STARTING THE PROGRAMMED DSCNT AS EXPECTED NEAR STW, PA.

Narrative: ON FLT FROM LAX TO JFK, WE WERE CRUISING AT FL370. WE WERE ASSIGNED TO CROSS HARTY INTXN ON THE LENDY 4 ARR TO JFK AT FL230. THE ACFT WAS ON AUTOPLT AND IN VNAV. THE EXPECTED CLRNC ALTS WERE PREVIOUSLY PROGRAMMED INTO THE FMC. UPON RECEIVING THE XING RESTR AT HARTY, THE CAPT ENTERED FL230 IN THE FMC CRUISE PAGE AND EXECUTED THE INSTRUCTION. THE MCP ALT WAS SET TO FL230. I NOTIFIED CTR WE WERE LEAVING FL370 TO FL230. AT THIS TIME I RESUMED MY PNF DUTIES OF UPDATING THE ATIS AND MAKING A FINAL PA TO THE PAX. WHEN I FINISHED, I NOTED THE ACFT WAS STILL AT FL370 AND ONLY 10 MI OR SO TO HARTY. I NOTIFIED THE CAPT, WHO STARTED AN IMMEDIATE DSCNT IN FLT LEVEL CHANGE MODE. I THEN NOTIFIED ATC THAT WE WOULD NOT MAKE THE XING RESTR AT HARTY, AS WE DID HAVE ABOUT AN 80 KT TAILWIND AT THE TIME. WE CROSSED HARTY SOME 1500-2000 FT HIGH. TO MY KNOWLEDGE, NO LOSS OF SEPARATION OCCURRED. THE POINT OF THIS RPT IS THAT THE AUTOMATION IN MODERN AIRLINERS IS GREAT, AND IN MY EXPERIENCE WORKS CORRECTLY 99.9% OF THE TIME. THIS SUCCESS RATE LULLS US INTO COMPLACENCY, BELIEVING THE SYS WILL ALWAYS DO WHAT WE HAVE PROGRAMMED IT TO DO. WHEN USING THE AUTOMATION, HOWEVER, WE SHOULD BE EXTRA VIGILANT TO ENSURE THE AUTOMATION DOES DO WHAT WE WANT IT TO DO! I STILL DON'T KNOW WHY THE ACFT REMAINED AT FL370 WHEN THE NEW CRUISE ALT WAS SET TO FL230. THE FAILURE HERE, HOWEVER, WAS THAT WE FAILED TO NOTICE IMMEDIATELY THAT THE SYS WAS NOT DOING WHAT WE WANTED IT TO DO.

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.