Narrative:

While flying inbound on the 'skebr RNAV 2 arrival' I was high at the crossing restr at the misen arrival fix. The problem was that in the FMGC on the airbus, the entire RNAV arrival is built in the box as depicted on the plate. That plate actually says to cross misen at or above FL240. I believe that the controller gave us misen at FL240. The computer wanted to cross 'at or above.' by the time I realized the error, I hurried down to cross misen at FL240. Bottom line is that I was higher than FL240 when we crossed. While this would be considered pilot error, I believe that there are some problems and/or confusion often associated with these RNAV arrs. They work pretty well when you can just fly them as they are depicted (which I believed was the whole point to them). In real life, they don't usually leave you on them. The controllers change some parts of them -- usually altitudes -- to fit in somehow with other traffic. Clearing you for a 'pre canned' arrival then later changing parts of it, seems to me to be setting you up to miss something. I think that we should either fly the arrs as depicted or go back to the old arrs without all of the preassigned altitudes.

Google
 

Original NASA ASRS Text

Title: A320 FLT CREW UNANTICIPATED ZLA CLRNC CHANGE TO SKEBR RNAV STAR CAUSES LATE RECOGNITION TO CORRECT FMS PROGRAMMING TO MEET AMENDED MISEN INTXN XING RESTR.

Narrative: WHILE FLYING INBOUND ON THE 'SKEBR RNAV 2 ARR' I WAS HIGH AT THE XING RESTR AT THE MISEN ARR FIX. THE PROB WAS THAT IN THE FMGC ON THE AIRBUS, THE ENTIRE RNAV ARR IS BUILT IN THE BOX AS DEPICTED ON THE PLATE. THAT PLATE ACTUALLY SAYS TO CROSS MISEN AT OR ABOVE FL240. I BELIEVE THAT THE CTLR GAVE US MISEN AT FL240. THE COMPUTER WANTED TO CROSS 'AT OR ABOVE.' BY THE TIME I REALIZED THE ERROR, I HURRIED DOWN TO CROSS MISEN AT FL240. BOTTOM LINE IS THAT I WAS HIGHER THAN FL240 WHEN WE CROSSED. WHILE THIS WOULD BE CONSIDERED PLT ERROR, I BELIEVE THAT THERE ARE SOME PROBS AND/OR CONFUSION OFTEN ASSOCIATED WITH THESE RNAV ARRS. THEY WORK PRETTY WELL WHEN YOU CAN JUST FLY THEM AS THEY ARE DEPICTED (WHICH I BELIEVED WAS THE WHOLE POINT TO THEM). IN REAL LIFE, THEY DON'T USUALLY LEAVE YOU ON THEM. THE CTLRS CHANGE SOME PARTS OF THEM -- USUALLY ALTS -- TO FIT IN SOMEHOW WITH OTHER TFC. CLRING YOU FOR A 'PRE CANNED' ARR THEN LATER CHANGING PARTS OF IT, SEEMS TO ME TO BE SETTING YOU UP TO MISS SOMETHING. I THINK THAT WE SHOULD EITHER FLY THE ARRS AS DEPICTED OR GO BACK TO THE OLD ARRS WITHOUT ALL OF THE PREASSIGNED ALTS.

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.