Narrative:

After takeoff from sea-tac, approximately 6 NM south, departure control clrd air carrier to turn left to 130 degrees to intercept the summa 2 departure as filed. After changing to center frequency sea center asked us if we were given a vector. We replied in the affirmative, we were given a heading to intercept the summa 2 departure as filed. We were given a right turn with the explanation that we were being vectored away from mt rainier (at the time of turn we had mt rainier on radar at 20 NM and our altitude was 15000', so we were not concerned with terrain clearance). After the turn we were clrd to intercept the summa 2 departure, as filed. After reviewing the summa 2 departure it appears we were expected to intercept the 143 degree radial of sea, after receiving a heading of 130 degrees, then to summa and the departure as filed, but our HSI did not indicate this. The FMS data base should be changed to reflect this. Our HSI, after the left turn to 130 degrees, showed that we would intercept the departure between summa and pendleton. Although I do not feel that our aircraft was ever in danger on this particular flight, I can see where this type of problem could become serious under other circumstances. Supplemental information from acn 80294: I feel that a human factors type of situation exists that causes large transport type aircraft pilots to feel that the 130 degree heading short of the 11 DME is a heading to the pendleton transition. It could be eliminated with a clearance to intercept the 143 degree radial, or a clearance to summa.

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Original NASA ASRS Text

Title: ACR LGT TRACK DEVIATION ON DEP.

Narrative: AFTER TKOF FROM SEA-TAC, APPROX 6 NM S, DEP CTL CLRD ACR TO TURN LEFT TO 130 DEGS TO INTERCEPT THE SUMMA 2 DEP AS FILED. AFTER CHANGING TO CENTER FREQ SEA CENTER ASKED US IF WE WERE GIVEN A VECTOR. WE REPLIED IN THE AFFIRMATIVE, WE WERE GIVEN A HDG TO INTERCEPT THE SUMMA 2 DEP AS FILED. WE WERE GIVEN A RIGHT TURN WITH THE EXPLANATION THAT WE WERE BEING VECTORED AWAY FROM MT RAINIER (AT THE TIME OF TURN WE HAD MT RAINIER ON RADAR AT 20 NM AND OUR ALT WAS 15000', SO WE WERE NOT CONCERNED WITH TERRAIN CLRNC). AFTER THE TURN WE WERE CLRD TO INTERCEPT THE SUMMA 2 DEP, AS FILED. AFTER REVIEWING THE SUMMA 2 DEP IT APPEARS WE WERE EXPECTED TO INTERCEPT THE 143 DEG RADIAL OF SEA, AFTER RECEIVING A HDG OF 130 DEGS, THEN TO SUMMA AND THE DEP AS FILED, BUT OUR HSI DID NOT INDICATE THIS. THE FMS DATA BASE SHOULD BE CHANGED TO REFLECT THIS. OUR HSI, AFTER THE LEFT TURN TO 130 DEGS, SHOWED THAT WE WOULD INTERCEPT THE DEP BTWN SUMMA AND PENDLETON. ALTHOUGH I DO NOT FEEL THAT OUR ACFT WAS EVER IN DANGER ON THIS PARTICULAR FLT, I CAN SEE WHERE THIS TYPE OF PROB COULD BECOME SERIOUS UNDER OTHER CIRCUMSTANCES. SUPPLEMENTAL INFORMATION FROM ACN 80294: I FEEL THAT A HUMAN FACTORS TYPE OF SITUATION EXISTS THAT CAUSES LGT TYPE ACFT PLTS TO FEEL THAT THE 130 DEG HDG SHORT OF THE 11 DME IS A HDG TO THE PENDLETON TRANSITION. IT COULD BE ELIMINATED WITH A CLRNC TO INTERCEPT THE 143 DEG RADIAL, OR A CLRNC TO SUMMA.

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.