Narrative:

On an en route descent into dayton our clearance was direct rid VOR, direct dayton with a descent to 11000'. The controller gave us a new clearance to cross 10 mi west of rid at 10000'. The captain, being less experienced in using the flight management computer than I, wanted me to show him how to program the descent for new restrictions. We put the restriction in the magic box and for some reason, almost certainly something we did improperly, the machine wanted to make the restriction 10 mi east of rid. By the time we caught the error in the midst of doing checklists and the usual cockpit duties we were too late to make the restriction. Nothing was said and there was no conflict. There is no question that this mistake was our fault but it brings up a point. These whiz bang computers and flight management system are great, but you not only have to watch them like a hawk, they are a error waiting to spring. Flight management system as they are currently designed do the most and are easiest to use when you need them least; at cruise. The closer you are to the ground, that is on takeoff or approach, the more demanding of attention they are. Reprogramming for constantly changing clrncs, which happens most in the takeoff or approach phases distracts attention from outside and inside vigilance as well as steps up situations where mistakes are likely to occur as the workload increases. To be sure, the pilots are always responsible for making whatever restrictions there are, not the computers. If we're going to have these sophisticated and really wonderful machines in the cockpits design effort should be put into making them more useful and less prone to inducing errors in the takeoff and approach phases.

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Original NASA ASRS Text

Title: ACR MLG ALT DEVIATION UNDERSHOT ALT CROSSING RESTRICTION.

Narrative: ON AN ENRTE DSNT INTO DAYTON OUR CLRNC WAS DIRECT RID VOR, DIRECT DAYTON WITH A DSNT TO 11000'. THE CTLR GAVE US A NEW CLRNC TO CROSS 10 MI W OF RID AT 10000'. THE CAPT, BEING LESS EXPERIENCED IN USING THE FLT MGMNT COMPUTER THAN I, WANTED ME TO SHOW HIM HOW TO PROGRAM THE DSNT FOR NEW RESTRICTIONS. WE PUT THE RESTRICTION IN THE MAGIC BOX AND FOR SOME REASON, ALMOST CERTAINLY SOMETHING WE DID IMPROPERLY, THE MACHINE WANTED TO MAKE THE RESTRICTION 10 MI E OF RID. BY THE TIME WE CAUGHT THE ERROR IN THE MIDST OF DOING CHKLISTS AND THE USUAL COCKPIT DUTIES WE WERE TOO LATE TO MAKE THE RESTRICTION. NOTHING WAS SAID AND THERE WAS NO CONFLICT. THERE IS NO QUESTION THAT THIS MISTAKE WAS OUR FAULT BUT IT BRINGS UP A POINT. THESE WHIZ BANG COMPUTERS AND FLT MGMNT SYS ARE GREAT, BUT YOU NOT ONLY HAVE TO WATCH THEM LIKE A HAWK, THEY ARE A ERROR WAITING TO SPRING. FLT MGMNT SYS AS THEY ARE CURRENTLY DESIGNED DO THE MOST AND ARE EASIEST TO USE WHEN YOU NEED THEM LEAST; AT CRUISE. THE CLOSER YOU ARE TO THE GND, THAT IS ON TKOF OR APCH, THE MORE DEMANDING OF ATTN THEY ARE. REPROGRAMMING FOR CONSTANTLY CHANGING CLRNCS, WHICH HAPPENS MOST IN THE TKOF OR APCH PHASES DISTRACTS ATTN FROM OUTSIDE AND INSIDE VIGILANCE AS WELL AS STEPS UP SITUATIONS WHERE MISTAKES ARE LIKELY TO OCCUR AS THE WORKLOAD INCREASES. TO BE SURE, THE PLTS ARE ALWAYS RESPONSIBLE FOR MAKING WHATEVER RESTRICTIONS THERE ARE, NOT THE COMPUTERS. IF WE'RE GOING TO HAVE THESE SOPHISTICATED AND REALLY WONDERFUL MACHINES IN THE COCKPITS DESIGN EFFORT SHOULD BE PUT INTO MAKING THEM MORE USEFUL AND LESS PRONE TO INDUCING ERRORS IN THE TKOF AND APCH PHASES.

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.