Narrative:

While in cruise at FL360; we were told to expect to cross turlo at FL240. I input that in the FMC. As ATC started stepping us down; we were changing 'cruise altitude' in the FMC. We did not use 'descend now' feature. That turned out to be a mistake. As we approached turlo; it became obvious that we were not going to be able to comply with the restr. ATC queried us whether we'll make the restr. We responded that we were not able to comply with it. The controller asked if we'd be able to level off at FL240 in 2 mins; which we could and did. We leveled off at FL240 in 1 min. There was no loss of separation; however; this was a very valuable lesson in use of automation -- use 'descend now' feature as opposed to changing 'cruise altitude.'

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Original NASA ASRS Text

Title: B737-700 FLT CREW DOES NOT MEET A XING RESTR INBOUND TO SMF.

Narrative: WHILE IN CRUISE AT FL360; WE WERE TOLD TO EXPECT TO CROSS TURLO AT FL240. I INPUT THAT IN THE FMC. AS ATC STARTED STEPPING US DOWN; WE WERE CHANGING 'CRUISE ALT' IN THE FMC. WE DID NOT USE 'DSND NOW' FEATURE. THAT TURNED OUT TO BE A MISTAKE. AS WE APCHED TURLO; IT BECAME OBVIOUS THAT WE WERE NOT GOING TO BE ABLE TO COMPLY WITH THE RESTR. ATC QUERIED US WHETHER WE'LL MAKE THE RESTR. WE RESPONDED THAT WE WERE NOT ABLE TO COMPLY WITH IT. THE CTLR ASKED IF WE'D BE ABLE TO LEVEL OFF AT FL240 IN 2 MINS; WHICH WE COULD AND DID. WE LEVELED OFF AT FL240 IN 1 MIN. THERE WAS NO LOSS OF SEPARATION; HOWEVER; THIS WAS A VERY VALUABLE LESSON IN USE OF AUTOMATION -- USE 'DSND NOW' FEATURE AS OPPOSED TO CHANGING 'CRUISE ALT.'

Data retrieved from NASA's ASRS site as of January 2009 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.