Narrative:

Small transport X departed runway 28 at pdx with intermittent mode C. I instructed small transport X leaving 2000' turn right heading 320 degrees. Small transport Y was inbound on the btg 310 right for pdx. I instructed small transport Y to depart btg heading 110 degrees and descend and maintain 10000'. I turned small transport X right heading 030 degrees proceed direct ykm when able, and maintain 7000' for traffic. Small transport X was filed pdx direct eat. I reclred small transport X heading 030 degrees direct eat when able. The pilot answered with thank you. Small transport Y climbed through 7000' directly under small transport Y leaving 8300 for 8000'. Small transport X was descended back to 7000' and issued traffic on small transport Y. Supplemental information from 85269: after departing and being turned over to departure control I was given a 30 degree right turn to 310 degrees. Soon after that I was told that my mode C altitude report was inoperative. I reset my transponder and was told that it was ok. I was then given another right turn to 030 degrees, cleared direct to yakima and I understood him to say maintain 9000'. I told him that I had filed direct to wenatchee, not yakima, and he cleared me into wenatchee. I climbed through 7000' on my way to 9000 when he asked me what my altitude was and that I had only been cleared to 7000' because of conflicting traffic. I told him that I had misunderstood and descended to 7100'. Since I was already cleared to 9000', I should have checked with the controller when I understood him to say 9000' a second time. I believe the mix up with my destination at the time he gave me a new altitude helped confuse things.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION WITH SMT CLIMBING AND SMT DESCENDING, CTL HAD GIVEN NEW HEADING AND ALT ASSIGNMENT THAT WAS MISSED.

Narrative: SMT X DEPARTED RWY 28 AT PDX WITH INTERMITTENT MODE C. I INSTRUCTED SMT X LEAVING 2000' TURN RIGHT HDG 320 DEGS. SMT Y WAS INBND ON THE BTG 310 R FOR PDX. I INSTRUCTED SMT Y TO DEPART BTG HDG 110 DEGS AND DSND AND MAINTAIN 10000'. I TURNED SMT X RIGHT HDG 030 DEGS PROCEED DIRECT YKM WHEN ABLE, AND MAINTAIN 7000' FOR TFC. SMT X WAS FILED PDX DIRECT EAT. I RECLRED SMT X HDG 030 DEGS DIRECT EAT WHEN ABLE. THE PLT ANSWERED WITH THANK YOU. SMT Y CLBED THROUGH 7000' DIRECTLY UNDER SMT Y LEAVING 8300 FOR 8000'. SMT X WAS DSNDED BACK TO 7000' AND ISSUED TFC ON SMT Y. SUPPLEMENTAL INFO FROM 85269: AFTER DEPARTING AND BEING TURNED OVER TO DEP CTL I WAS GIVEN A 30 DEG RIGHT TURN TO 310 DEGS. SOON AFTER THAT I WAS TOLD THAT MY MODE C ALT RPT WAS INOP. I RESET MY TRANSPONDER AND WAS TOLD THAT IT WAS OK. I WAS THEN GIVEN ANOTHER RIGHT TURN TO 030 DEGS, CLRED DIRECT TO YAKIMA AND I UNDERSTOOD HIM TO SAY MAINTAIN 9000'. I TOLD HIM THAT I HAD FILED DIRECT TO WENATCHEE, NOT YAKIMA, AND HE CLRED ME INTO WENATCHEE. I CLBED THROUGH 7000' ON MY WAY TO 9000 WHEN HE ASKED ME WHAT MY ALT WAS AND THAT I HAD ONLY BEEN CLRED TO 7000' BECAUSE OF CONFLICTING TFC. I TOLD HIM THAT I HAD MISUNDERSTOOD AND DSNDED TO 7100'. SINCE I WAS ALREADY CLRED TO 9000', I SHOULD HAVE CHKED WITH THE CTLR WHEN I UNDERSTOOD HIM TO SAY 9000' A SECOND TIME. I BELIEVE THE MIX UP WITH MY DEST AT THE TIME HE GAVE ME A NEW ALT HELPED CONFUSE THINGS.

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.