Narrative:

We have just started using 'descend via' procedures on the arrs into atlanta. This was the second time I had been assigned one; the first on the erlin. We had done the honie arrival earlier in the day. My captain had done the 'descend via' procedures on a trip the previous 2 days; and had briefed me that the vertical guidance on the airplane did not seem to be accurate -- they had to dive to make crossing restrs when they tried to follow it. We crossed erlin at 12000 ft; both very focused on what came next. We crossed stutz at 250 KTS and discussed nofiv at 210 KTS. I had already set the altitude alerter to 7000 ft for the restr at fanew; the next 'new' altitude we needed. We were trying to stay ahead of the game. We knew the distance to start down from 12000 ft to 7000 ft on a 3 degree glide path is 15 mi. Not trusting our VNAV; we chose that as our point to start down; because we were so worried about missing that crossing restr at fanew; which is actually an 'at or above' -- we even verbally noted that; but it didn't sink in that we did not 'need' to be there 'at' 7000 ft. My captain started slowing for the 210 KT restr at nofiv; and at 3 mi prior to nofiv started his descent (15 mi prior to fanew). I looked over to check my chart to verify everything was correct; and I then noticed we were to cross nofiv at 12000 ft. We were at 11700 ft and descending. I called out to stop; my captain noticed it at the same time and stopped the descent. ATC then cleared us to 11000 ft; and pointed out we were to cross nofiv at 12000 ft. He said to cross nofiv at 11000 ft now and descend via the erlin 5. The captain and I decided we should not have been so anxious about setting the next altitude. Obviously we should have left the altitude alerter at 12000 ft until after nofiv; and it should have registered that although we can't make a 3 degree descent from 12000 ft to 7000 ft in 11.9 mi (the distance from nofiv to fanew); we didn't have to -- we would be above 7000 ft and that was acceptable. We both agreed that 'next time;' instead of ever setting 7000 ft; we would set the 5000 ft restr at havad and descend on a 3 degree path for that crossing; which would put us well above 7000 ft at fanew. We were trying very hard to be precise and it was an unfamiliar procedure for us. We distrusted our automation due to the captain's previous experience. Also; the captain (PF) had previously done the honie 5 and canuk 6 arrs as 'descend via' procedures; both of which 'do' require a descent from the 40 mi fix (honie and canuk) to the corner fix (fogog and bojaa). I think this put us in a mindset that these arrs all required this; based on our few previous experiences. The erlin was the first one that did not require this intermediate descent. We should have been more alert to this difference. We did thoroughly discuss the arrival; our plan; and the setting of the altitude alerter to the 'next' altitude after erlin. We both agreed on everything; and we missed that 12000 ft should still be in there for nofiv; or that we could not start down until after it. I do think a contributing factor was our mindset of always having to be at an altitude. I can't remember ever coming into atlanta in 7 yrs and being told to cross something 'at or above' an altitude. It has always been 'at or below;' ie; 'cross honie at or below 14000 ft; descend and maintain 12000 ft.' we are programmed to 'make' our crossing restrs; and are typically worried about being too high; not too low. I don't really see anything our company could have done to prevent this. We just should have been more aware; and have to learn from our experience.

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Original NASA ASRS Text

Title: A CRJ200 PILOT REPORTS CONFUSION AND UNFAMILIARITY WITH THE 'DESCEND VIA' CLRNC ARRIVALS INTO ATL.

Narrative: WE HAVE JUST STARTED USING 'DSND VIA' PROCS ON THE ARRS INTO ATLANTA. THIS WAS THE SECOND TIME I HAD BEEN ASSIGNED ONE; THE FIRST ON THE ERLIN. WE HAD DONE THE HONIE ARR EARLIER IN THE DAY. MY CAPT HAD DONE THE 'DSND VIA' PROCS ON A TRIP THE PREVIOUS 2 DAYS; AND HAD BRIEFED ME THAT THE VERT GUIDANCE ON THE AIRPLANE DID NOT SEEM TO BE ACCURATE -- THEY HAD TO DIVE TO MAKE XING RESTRS WHEN THEY TRIED TO FOLLOW IT. WE CROSSED ERLIN AT 12000 FT; BOTH VERY FOCUSED ON WHAT CAME NEXT. WE CROSSED STUTZ AT 250 KTS AND DISCUSSED NOFIV AT 210 KTS. I HAD ALREADY SET THE ALT ALERTER TO 7000 FT FOR THE RESTR AT FANEW; THE NEXT 'NEW' ALT WE NEEDED. WE WERE TRYING TO STAY AHEAD OF THE GAME. WE KNEW THE DISTANCE TO START DOWN FROM 12000 FT TO 7000 FT ON A 3 DEG GLIDE PATH IS 15 MI. NOT TRUSTING OUR VNAV; WE CHOSE THAT AS OUR POINT TO START DOWN; BECAUSE WE WERE SO WORRIED ABOUT MISSING THAT XING RESTR AT FANEW; WHICH IS ACTUALLY AN 'AT OR ABOVE' -- WE EVEN VERBALLY NOTED THAT; BUT IT DIDN'T SINK IN THAT WE DID NOT 'NEED' TO BE THERE 'AT' 7000 FT. MY CAPT STARTED SLOWING FOR THE 210 KT RESTR AT NOFIV; AND AT 3 MI PRIOR TO NOFIV STARTED HIS DSCNT (15 MI PRIOR TO FANEW). I LOOKED OVER TO CHK MY CHART TO VERIFY EVERYTHING WAS CORRECT; AND I THEN NOTICED WE WERE TO CROSS NOFIV AT 12000 FT. WE WERE AT 11700 FT AND DSNDING. I CALLED OUT TO STOP; MY CAPT NOTICED IT AT THE SAME TIME AND STOPPED THE DSCNT. ATC THEN CLRED US TO 11000 FT; AND POINTED OUT WE WERE TO CROSS NOFIV AT 12000 FT. HE SAID TO CROSS NOFIV AT 11000 FT NOW AND DSND VIA THE ERLIN 5. THE CAPT AND I DECIDED WE SHOULD NOT HAVE BEEN SO ANXIOUS ABOUT SETTING THE NEXT ALT. OBVIOUSLY WE SHOULD HAVE LEFT THE ALT ALERTER AT 12000 FT UNTIL AFTER NOFIV; AND IT SHOULD HAVE REGISTERED THAT ALTHOUGH WE CAN'T MAKE A 3 DEG DSCNT FROM 12000 FT TO 7000 FT IN 11.9 MI (THE DISTANCE FROM NOFIV TO FANEW); WE DIDN'T HAVE TO -- WE WOULD BE ABOVE 7000 FT AND THAT WAS ACCEPTABLE. WE BOTH AGREED THAT 'NEXT TIME;' INSTEAD OF EVER SETTING 7000 FT; WE WOULD SET THE 5000 FT RESTR AT HAVAD AND DSND ON A 3 DEG PATH FOR THAT XING; WHICH WOULD PUT US WELL ABOVE 7000 FT AT FANEW. WE WERE TRYING VERY HARD TO BE PRECISE AND IT WAS AN UNFAMILIAR PROC FOR US. WE DISTRUSTED OUR AUTOMATION DUE TO THE CAPT'S PREVIOUS EXPERIENCE. ALSO; THE CAPT (PF) HAD PREVIOUSLY DONE THE HONIE 5 AND CANUK 6 ARRS AS 'DSND VIA' PROCS; BOTH OF WHICH 'DO' REQUIRE A DSCNT FROM THE 40 MI FIX (HONIE AND CANUK) TO THE CORNER FIX (FOGOG AND BOJAA). I THINK THIS PUT US IN A MINDSET THAT THESE ARRS ALL REQUIRED THIS; BASED ON OUR FEW PREVIOUS EXPERIENCES. THE ERLIN WAS THE FIRST ONE THAT DID NOT REQUIRE THIS INTERMEDIATE DSCNT. WE SHOULD HAVE BEEN MORE ALERT TO THIS DIFFERENCE. WE DID THOROUGHLY DISCUSS THE ARR; OUR PLAN; AND THE SETTING OF THE ALT ALERTER TO THE 'NEXT' ALT AFTER ERLIN. WE BOTH AGREED ON EVERYTHING; AND WE MISSED THAT 12000 FT SHOULD STILL BE IN THERE FOR NOFIV; OR THAT WE COULD NOT START DOWN UNTIL AFTER IT. I DO THINK A CONTRIBUTING FACTOR WAS OUR MINDSET OF ALWAYS HAVING TO BE AT AN ALT. I CAN'T REMEMBER EVER COMING INTO ATLANTA IN 7 YRS AND BEING TOLD TO CROSS SOMETHING 'AT OR ABOVE' AN ALT. IT HAS ALWAYS BEEN 'AT OR BELOW;' IE; 'CROSS HONIE AT OR BELOW 14000 FT; DSND AND MAINTAIN 12000 FT.' WE ARE PROGRAMMED TO 'MAKE' OUR XING RESTRS; AND ARE TYPICALLY WORRIED ABOUT BEING TOO HIGH; NOT TOO LOW. I DON'T REALLY SEE ANYTHING OUR COMPANY COULD HAVE DONE TO PREVENT THIS. WE JUST SHOULD HAVE BEEN MORE AWARE; AND HAVE TO LEARN FROM OUR EXPERIENCE.

Data retrieved from NASA's ASRS site as of May 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.