Narrative:

After passing the civet fix (lax 068/052) we were cleared for the reedr arrival. After deviations around a buildup on the arrival we were given a heading to re-intercept the arrival and a descent clearance to 10000 ft. Having never flown this arrival before, I was a little uncomfortable. I had the captain reconfirm the arrival clearance which she did and yes, we were cleared for the arrival. We passed the baset fix at 10000 ft. The captain then set 8000 ft in the altitude alert window and stated, 'cleared to 8000 ft by reedr.' something just didn't feel right, but I couldn't put my finger on it. So, I asked for 1 more confirmation from ATC in the hope something would be said to relieve my apprehension. ATC reconfirmed, 'cleared for arrival.' so, I began descending to 8000 ft and, at about 9500 ft, ATC said, 'xx maintain 10000.' he said, 'those are expected altitudes.' all of a sudden the light came on and I realized why I didn't feel comfortable. That is the gist of what happened. Now, why I think it happened: this happened on sunday afternoon. This sequence (trip) started fri night at late pm local at lax. West flew to chicago, had a 1 plus 15 ground time, then flew to hartford, ct, for about an AM00 local arrival. The next morning we have an AM15 departure. This type of scheduling has absolutely no regard for the body clock. Up all night one night, then the next day an early am (body clock) departure. This was the fourth trip of the month like this and it finally caught up with us. I knew something didn't feel right about the arrival procedure, but I couldn't' figure it out. Supplemental information from acn 256653: I feel there were 3 major factors involved which caused our error. The break from what STAR we were expecting and were accustomed to always flying into lax, the distraction of the unexpected storm cells during a key point at the beginning of the STAR, and mostly, our fatigue. The best and most logical solution to preventing such an occurrence in the future would be to use better trip construction to eliminate trips that change time schedule for the rest so frequently, and haven't much rest time between trips. The effects of fatigue and circadian rhythm disruptions are often a factor in accidents, and I believe that reducing fatigue results in fewer mistakes and the accidents that are caused by them.

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Original NASA ASRS Text

Title: FLC ON STAR INTO LAX HAS ALTDEV.

Narrative: AFTER PASSING THE CIVET FIX (LAX 068/052) WE WERE CLRED FOR THE REEDR ARR. AFTER DEVS AROUND A BUILDUP ON THE ARR WE WERE GIVEN A HDG TO RE-INTERCEPT THE ARR AND A DSCNT CLRNC TO 10000 FT. HAVING NEVER FLOWN THIS ARR BEFORE, I WAS A LITTLE UNCOMFORTABLE. I HAD THE CAPT RECONFIRM THE ARR CLRNC WHICH SHE DID AND YES, WE WERE CLRED FOR THE ARR. WE PASSED THE BASET FIX AT 10000 FT. THE CAPT THEN SET 8000 FT IN THE ALT ALERT WINDOW AND STATED, 'CLRED TO 8000 FT BY REEDR.' SOMETHING JUST DIDN'T FEEL RIGHT, BUT I COULDN'T PUT MY FINGER ON IT. SO, I ASKED FOR 1 MORE CONFIRMATION FROM ATC IN THE HOPE SOMETHING WOULD BE SAID TO RELIEVE MY APPREHENSION. ATC RECONFIRMED, 'CLRED FOR ARR.' SO, I BEGAN DSNDING TO 8000 FT AND, AT ABOUT 9500 FT, ATC SAID, 'XX MAINTAIN 10000.' HE SAID, 'THOSE ARE EXPECTED ALTS.' ALL OF A SUDDEN THE LIGHT CAME ON AND I REALIZED WHY I DIDN'T FEEL COMFORTABLE. THAT IS THE GIST OF WHAT HAPPENED. NOW, WHY I THINK IT HAPPENED: THIS HAPPENED ON SUNDAY AFTERNOON. THIS SEQUENCE (TRIP) STARTED FRI NIGHT AT LATE PM LCL AT LAX. W FLEW TO CHICAGO, HAD A 1 PLUS 15 GND TIME, THEN FLEW TO HARTFORD, CT, FOR ABOUT AN AM00 LCL ARR. THE NEXT MORNING WE HAVE AN AM15 DEP. THIS TYPE OF SCHEDULING HAS ABSOLUTELY NO REGARD FOR THE BODY CLOCK. UP ALL NIGHT ONE NIGHT, THEN THE NEXT DAY AN EARLY AM (BODY CLOCK) DEP. THIS WAS THE FOURTH TRIP OF THE MONTH LIKE THIS AND IT FINALLY CAUGHT UP WITH US. I KNEW SOMETHING DIDN'T FEEL RIGHT ABOUT THE ARR PROC, BUT I COULDN'T' FIGURE IT OUT. SUPPLEMENTAL INFO FROM ACN 256653: I FEEL THERE WERE 3 MAJOR FACTORS INVOLVED WHICH CAUSED OUR ERROR. THE BREAK FROM WHAT STAR WE WERE EXPECTING AND WERE ACCUSTOMED TO ALWAYS FLYING INTO LAX, THE DISTR OF THE UNEXPECTED STORM CELLS DURING A KEY POINT AT THE BEGINNING OF THE STAR, AND MOSTLY, OUR FATIGUE. THE BEST AND MOST LOGICAL SOLUTION TO PREVENTING SUCH AN OCCURRENCE IN THE FUTURE WOULD BE TO USE BETTER TRIP CONSTRUCTION TO ELIMINATE TRIPS THAT CHANGE TIME SCHEDULE FOR THE REST SO FREQUENTLY, AND HAVEN'T MUCH REST TIME BTWN TRIPS. THE EFFECTS OF FATIGUE AND CIRCADIAN RHYTHM DISRUPTIONS ARE OFTEN A FACTOR IN ACCIDENTS, AND I BELIEVE THAT REDUCING FATIGUE RESULTS IN FEWER MISTAKES AND THE ACCIDENTS THAT ARE CAUSED BY THEM.

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.