Narrative:

Prior to engine start, the crew discussed the discrepancies between the sea (20-3B), dated: 5/31/89, summa 2 departure page for runways 34L/right and the sea (20-7), dated: 4/28/89 airport information page for runways 34L/right. Specifically, the departure page (20-3B) calls for a right turn after proceeding to: 'cross seattle 8 DME fix at or above 4000';' whereas the airport information page 20-7) calls for the crew to: 'plan to be above 8000' and 4 mi from the airport before turning northeast.' the transposed distances and altitudes on the (20-7) page were a direct factor in triggering the crew into initiating the right turn after the 4 DME distance and 4000' as opposed to the correct 8 DME distance. An additional confusing factor on the airport information page is the use of the word 'plan' when speaking of an altitude and distance crossing requirement. This gives a 'may' connotation as opposed to a 'required' connotation. In this situation, with the transposed #'south, one is left with the subconscious idea that either distance or altitude could trigger the course change, instead of a distance and altitude requirement. With the normal activity and procedures of an IFR departure, conflicting and transposed data set a potentially dangerous mental trap for a busy flight crew. If the individuals sitting at a non moving desk/computer cannot enter the (20-7) information correctly, how can we expect line crews to actually fly the IFR departure procedures using such conflicting information? Supplemental information from acn 110620: subsequent investigation shows that page 20-7 is generated by a single person using a word processor rather than the staff and data base used for all other pages. A potentially costly cost saving measure.

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Original NASA ASRS Text

Title: FLT CREW OF WDB DEPARTING SEA STARTED TURN AT WRONG MILEAGE FROM ARPT.

Narrative: PRIOR TO ENG START, THE CREW DISCUSSED THE DISCREPANCIES BTWN THE SEA (20-3B), DATED: 5/31/89, SUMMA 2 DEP PAGE FOR RWYS 34L/R AND THE SEA (20-7), DATED: 4/28/89 ARPT INFO PAGE FOR RWYS 34L/R. SPECIFICALLY, THE DEP PAGE (20-3B) CALLS FOR A RIGHT TURN AFTER PROCEEDING TO: 'CROSS SEATTLE 8 DME FIX AT OR ABOVE 4000';' WHEREAS THE ARPT INFO PAGE 20-7) CALLS FOR THE CREW TO: 'PLAN TO BE ABOVE 8000' AND 4 MI FROM THE ARPT BEFORE TURNING NE.' THE TRANSPOSED DISTANCES AND ALTS ON THE (20-7) PAGE WERE A DIRECT FACTOR IN TRIGGERING THE CREW INTO INITIATING THE RIGHT TURN AFTER THE 4 DME DISTANCE AND 4000' AS OPPOSED TO THE CORRECT 8 DME DISTANCE. AN ADDITIONAL CONFUSING FACTOR ON THE ARPT INFO PAGE IS THE USE OF THE WORD 'PLAN' WHEN SPEAKING OF AN ALT AND DISTANCE XING REQUIREMENT. THIS GIVES A 'MAY' CONNOTATION AS OPPOSED TO A 'REQUIRED' CONNOTATION. IN THIS SITUATION, WITH THE TRANSPOSED #'S, ONE IS LEFT WITH THE SUBCONSCIOUS IDEA THAT EITHER DISTANCE OR ALT COULD TRIGGER THE COURSE CHANGE, INSTEAD OF A DISTANCE AND ALT REQUIREMENT. WITH THE NORMAL ACTIVITY AND PROCS OF AN IFR DEP, CONFLICTING AND TRANSPOSED DATA SET A POTENTIALLY DANGEROUS MENTAL TRAP FOR A BUSY FLT CREW. IF THE INDIVIDUALS SITTING AT A NON MOVING DESK/COMPUTER CANNOT ENTER THE (20-7) INFO CORRECTLY, HOW CAN WE EXPECT LINE CREWS TO ACTUALLY FLY THE IFR DEP PROCS USING SUCH CONFLICTING INFO? SUPPLEMENTAL INFO FROM ACN 110620: SUBSEQUENT INVESTIGATION SHOWS THAT PAGE 20-7 IS GENERATED BY A SINGLE PERSON USING A WORD PROCESSOR RATHER THAN THE STAFF AND DATA BASE USED FOR ALL OTHER PAGES. A POTENTIALLY COSTLY COST SAVING MEASURE.

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