Narrative:

Air carrier X climbing over vhp was given a vector to 340 degrees for climb to FL310, then a vector of 310 degrees was given. Also, ATC cleared air carrier X to a heading of 265 degrees for capture upon leaving FL250. Upon leaving FL250 I turned to a heading of 265 degrees as instructed. While in a slow turn, TCASII (TA/RA) advised to climb (it was in a slow climb at the time). ATC then instructed me to turn to a heading of 360 degrees for traffic Y. Approximately 2 mins later I was given a heading of 265 degrees for cap. There was a misunderstanding (communication) as ATC stated that the clearance he gave was upon leaving FL270, then a heading of 265 degrees. Both myself and the copilot heard FL250 in lieu of FL270. No traffic was seen. Upon arriving in sea on approach to runway 34 at 1500 ft AGL, the TCASII again gave TA and climb. No traffic was seen or reported by tower. I squawked the TCASII unit to maintenance. Supplemental information from acn 251305: air carrier X climbing out of cvg assigned 320 degree heading climbed to FL310. Traffic was nwbound at FL260. Air carrier X issued 265 degrees, receiving cap (heading) after leaving FL270. Air carrier X turned to the heading. Leaving FL250 separation was lost with air carrier Y FL260.

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Original NASA ASRS Text

Title: ACR X NON ADHERENCE TO ATC CLRNC TURNED AT WRONG ALT HAD LTSS FROM ACR Y. SYS ERROR. ACR X FALSE TCASII RA. ACFT EQUIP PROB TCASII.

Narrative: ACR X CLBING OVER VHP WAS GIVEN A VECTOR TO 340 DEGS FOR CLB TO FL310, THEN A VECTOR OF 310 DEGS WAS GIVEN. ALSO, ATC CLRED ACR X TO A HDG OF 265 DEGS FOR CAPTURE UPON LEAVING FL250. UPON LEAVING FL250 I TURNED TO A HDG OF 265 DEGS AS INSTRUCTED. WHILE IN A SLOW TURN, TCASII (TA/RA) ADVISED TO CLB (IT WAS IN A SLOW CLB AT THE TIME). ATC THEN INSTRUCTED ME TO TURN TO A HDG OF 360 DEGS FOR TFC Y. APPROX 2 MINS LATER I WAS GIVEN A HDG OF 265 DEGS FOR CAP. THERE WAS A MISUNDERSTANDING (COM) AS ATC STATED THAT THE CLRNC HE GAVE WAS UPON LEAVING FL270, THEN A HDG OF 265 DEGS. BOTH MYSELF AND THE COPLT HEARD FL250 IN LIEU OF FL270. NO TFC WAS SEEN. UPON ARRIVING IN SEA ON APCH TO RWY 34 AT 1500 FT AGL, THE TCASII AGAIN GAVE TA AND CLB. NO TFC WAS SEEN OR RPTED BY TWR. I SQUAWKED THE TCASII UNIT TO MAINT. SUPPLEMENTAL INFO FROM ACN 251305: ACR X CLBING OUT OF CVG ASSIGNED 320 DEG HDG CLBED TO FL310. TFC WAS NWBOUND AT FL260. ACR X ISSUED 265 DEGS, RECEIVING CAP (HDG) AFTER LEAVING FL270. ACR X TURNED TO THE HDG. LEAVING FL250 SEPARATION WAS LOST WITH ACR Y FL260.

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