Narrative:

Prior to departure crew received pre departure clearance that read as follows: -WEVIC1 ksino GRNPA1; klas; kslc WEVIC1 dat mlf; GRNPA1; klas; edct; WEVIC1 departure; maintain 14000; maintain 230 KTS. Discussion occurred between the first officer and captain as to the intent of the change indicated by WEVIC1 ksino GRANPA1 klas. First officer concluded that the change did not indicate a point to exit the WEVIC1 and proceed direct to ksino as the change seemed to indicate. Upon review of the SID; I determined that the intent was to fly the route as filed but truncate the GRANPA1 arrival by proceeding direct to ksino after the completion of the WEVIC1 departure as filed. I failed to note during the crew discussion/review that there was indeed a ksino transition associated with the WEVIC1 departure and therefore entered the route to depart the SID by turning from loudy to dta and then direct ksino. The actual intent of the revised clearance was to maintain the WEVIC1 departure all the way to ksino. Upon making the turn at loudy; ATC issued a vector to 090 degrees and climb to FL320 to avoid an impending traffic conflict with an aircraft inbound to slc. We were informed that separation was never lost and that this error has occurred multiple times in the past. This was clearly an interpretation error of the intended clearance on my part. The entire situation would...we will invariably get from ATC. The final point I would make is that the ATC controller indicated that we were; by far; not the first aircraft to make this error. He in fact stated that the error had been made 'at least 10 times in the last month!' we must determine a method to ensure that once an error trend is revealed; immediate steps are taken to modify procedures or; at a minimum; highlight the potential error to flight crews that will be exposed to that environment. Supplemental information from acn 802629: made turn to dta on WEVIC1 departure instead of continuing on the WEVIC1 to ksino. ATC vector to ksino cleared on course and no further instructions. The clearance needs to be changed to not include dta. File the clearance as they want it flown. Callback conversation with reporter revealed the following information: the first officer stressed the statement from ATC regarding this being 'at least' the tenth time that month this had happened. He felt that by the fourth or fifth time something would/should have been done to prevent it. Reporter advised his aircraft did not have an operative printer to provide a hard copy of the clearance and that the clearance required at least two and perhaps three CDU display screens to be hand copied for review with the captain. He felt the flight crew had reviewed; interpreted; and resolved the intent of the message; only to discover enroute that their interpretation was flawed. He has made it a personal rule that; henceforth; any time there is an indication of a revised route he will call clearance delivery to assure proper understanding. He felt that repeated cases of pre departure clearance 'revised segments' that actually revised nothing had programmed him to be less diligent in reviewing them closely enough. He used the phrase 'negative training' to address this effect. He advised that; unlike printed 'plain language headers' used by most carriers; to specify the 'filed route;' and/or the 'cleared/revised' route; the CDU screens provide no such distinction; relying on 'coded symbology' to differentiate between them. He also expressed his personal feeling that the frequent inclusion of revised segments that do not actually 'revise' the route might be the result of a difference in the manner in which the company formats a 'canned' city pair route and the format for that same route utilized by ATC. He feels that restating the same route in a different way predisposes the flight crew to assume there is actually something 'revised' which leads them to arrive at incorrect interpretations. He stressed his displeasure at the continued use of 'coding' vice plain language -- especially coding that is subject to interpretation or assumption. He doesn't understand why the pre departure clearance includes any information other than identification information and the routethey are cleared to navigate ... The same thing they would get if they called clearance delivery.

Related reports:

Google
 

Original NASA ASRS Text

Title: MISINTERPRETATION OF PDC CLRNC BY FO RESULTS IN FLT CREW'S FAILURE TO FOLLOW CLRED SID TRANSITION.

Narrative: PRIOR TO DEP CREW RECEIVED PDC THAT READ AS FOLLOWS: -WEVIC1 KSINO GRNPA1; KLAS; KSLC WEVIC1 DAT MLF; GRNPA1; KLAS; EDCT; WEVIC1 DEP; MAINTAIN 14000; MAINTAIN 230 KTS. DISCUSSION OCCURRED BTWN THE FO AND CAPT AS TO THE INTENT OF THE CHANGE INDICATED BY WEVIC1 KSINO GRANPA1 KLAS. FO CONCLUDED THAT THE CHANGE DID NOT INDICATE A POINT TO EXIT THE WEVIC1 AND PROCEED DIRECT TO KSINO AS THE CHANGE SEEMED TO INDICATE. UPON REVIEW OF THE SID; I DETERMINED THAT THE INTENT WAS TO FLY THE RTE AS FILED BUT TRUNCATE THE GRANPA1 ARR BY PROCEEDING DIRECT TO KSINO AFTER THE COMPLETION OF THE WEVIC1 DEP AS FILED. I FAILED TO NOTE DURING THE CREW DISCUSSION/REVIEW THAT THERE WAS INDEED A KSINO TRANSITION ASSOCIATED WITH THE WEVIC1 DEP AND THEREFORE ENTERED THE RTE TO DEPART THE SID BY TURNING FROM LOUDY TO DTA AND THEN DIRECT KSINO. THE ACTUAL INTENT OF THE REVISED CLRNC WAS TO MAINTAIN THE WEVIC1 DEP ALL THE WAY TO KSINO. UPON MAKING THE TURN AT LOUDY; ATC ISSUED A VECTOR TO 090 DEGS AND CLB TO FL320 TO AVOID AN IMPENDING TFC CONFLICT WITH AN ACFT INBOUND TO SLC. WE WERE INFORMED THAT SEPARATION WAS NEVER LOST AND THAT THIS ERROR HAS OCCURRED MULTIPLE TIMES IN THE PAST. THIS WAS CLRLY AN INTERP ERROR OF THE INTENDED CLRNC ON MY PART. THE ENTIRE SITUATION WOULD...WE WILL INVARIABLY GET FROM ATC. THE FINAL POINT I WOULD MAKE IS THAT THE ATC CTLR INDICATED THAT WE WERE; BY FAR; NOT THE FIRST ACFT TO MAKE THIS ERROR. HE IN FACT STATED THAT THE ERROR HAD BEEN MADE 'AT LEAST 10 TIMES IN THE LAST MONTH!' WE MUST DETERMINE A METHOD TO ENSURE THAT ONCE AN ERROR TREND IS REVEALED; IMMEDIATE STEPS ARE TAKEN TO MODIFY PROCS OR; AT A MINIMUM; HIGHLIGHT THE POTENTIAL ERROR TO FLT CREWS THAT WILL BE EXPOSED TO THAT ENVIRONMENT. SUPPLEMENTAL INFO FROM ACN 802629: MADE TURN TO DTA ON WEVIC1 DEP INSTEAD OF CONTINUING ON THE WEVIC1 TO KSINO. ATC VECTOR TO KSINO CLRED ON COURSE AND NO FURTHER INSTRUCTIONS. THE CLRNC NEEDS TO BE CHANGED TO NOT INCLUDE DTA. FILE THE CLRNC AS THEY WANT IT FLOWN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE FO STRESSED THE STATEMENT FROM ATC REGARDING THIS BEING 'AT LEAST' THE TENTH TIME THAT MONTH THIS HAD HAPPENED. HE FELT THAT BY THE FOURTH OR FIFTH TIME SOMETHING WOULD/SHOULD HAVE BEEN DONE TO PREVENT IT. REPORTER ADVISED HIS ACFT DID NOT HAVE AN OPERATIVE PRINTER TO PROVIDE A HARD COPY OF THE CLRNC AND THAT THE CLRNC REQUIRED AT LEAST TWO AND PERHAPS THREE CDU DISPLAY SCREENS TO BE HAND COPIED FOR REVIEW WITH THE CAPTAIN. HE FELT THE FLT CREW HAD REVIEWED; INTERPRETED; AND RESOLVED THE INTENT OF THE MESSAGE; ONLY TO DISCOVER ENROUTE THAT THEIR INTERPRETATION WAS FLAWED. HE HAS MADE IT A PERSONAL RULE THAT; HENCEFORTH; ANY TIME THERE IS AN INDICATION OF A REVISED ROUTE HE WILL CALL CLRNC DELIVERY TO ASSURE PROPER UNDERSTANDING. HE FELT THAT REPEATED CASES OF PDC 'REVISED SEGMENTS' THAT ACTUALLY REVISED NOTHING HAD PROGRAMMED HIM TO BE LESS DILIGENT IN REVIEWING THEM CLOSELY ENOUGH. HE USED THE PHRASE 'NEGATIVE TRAINING' TO ADDRESS THIS EFFECT. HE ADVISED THAT; UNLIKE PRINTED 'PLAIN LANGUAGE HEADERS' USED BY MOST CARRIERS; TO SPECIFY THE 'FILED ROUTE;' AND/OR THE 'CLEARED/REVISED' ROUTE; THE CDU SCREENS PROVIDE NO SUCH DISTINCTION; RELYING ON 'CODED SYMBOLOGY' TO DIFFERENTIATE BETWEEN THEM. HE ALSO EXPRESSED HIS PERSONAL FEELING THAT THE FREQUENT INCLUSION OF REVISED SEGMENTS THAT DO NOT ACTUALLY 'REVISE' THE ROUTE MIGHT BE THE RESULT OF A DIFFERENCE IN THE MANNER IN WHICH THE COMPANY FORMATS A 'CANNED' CITY PAIR ROUTE AND THE FORMAT FOR THAT SAME ROUTE UTILIZED BY ATC. HE FEELS THAT RESTATING THE SAME ROUTE IN A DIFFERENT WAY PREDISPOSES THE FLT CREW TO ASSUME THERE IS ACTUALLY SOMETHING 'REVISED' WHICH LEADS THEM TO ARRIVE AT INCORRECT INTERPRETATIONS. HE STRESSED HIS DISPLEASURE AT THE CONTINUED USE OF 'CODING' VICE PLAIN LANGUAGE -- ESPECIALLY CODING THAT IS SUBJECT TO INTERPRETATION OR ASSUMPTION. HE DOESN'T UNDERSTAND WHY THE PDC INCLUDES ANY INFORMATION OTHER THAN IDENTIFICATION INFORMATION AND THE ROUTETHEY ARE CLEARED TO NAVIGATE ... THE SAME THING THEY WOULD GET IF THEY CALLED CLRNC DELIVERY.

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.