Narrative:

I had just completed 3 takeoffs and lndgs as part of a CFI-ase checkride and was departing to the west practice area to complete the airwork. I had requested 3500' as an en route altitude and had been cleared to climb and maintain 3000 as is usual for this area. I read back 3000' but somehow fixated on 3500'. As I was crossing through 3100' approach called traffic at 2 O'clock and 8 mi at 3500' which I spotted and responded with 'tallyho'. As I was crossing 3400' and beginning my level off, approach requested verification of altitude to which I responded 3500' and they promptly indicated that I had been cleared to 3000' and had read back 3000' and should have been at 3000. As soon as they told me that I was cleared to 3000', I realized my error, but not until then. I would have continued at 3500' without realizing it if they had not said anything. The airplane I was flying had functional mode C but by the time they said anything the other aircraft had passed behind me by about 1/2 mi at my altitude. I had the other aircraft in sight and was wondering about them bringing us that close together but assumed that we had legal separation since it is difficult to judge distance in flight especially when the other aircraft's type is unknown. No action was taken as non was felt necessary. Of course, I failed the checkride.

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Original NASA ASRS Text

Title: PLT ON INITIAL INSTRUCTOR CHECK RIDE CLIMBS THROUGH ASSIGNED ALT.

Narrative: I HAD JUST COMPLETED 3 TKOFS AND LNDGS AS PART OF A CFI-ASE CHECKRIDE AND WAS DEPARTING TO THE W PRACTICE AREA TO COMPLETE THE AIRWORK. I HAD REQUESTED 3500' AS AN ENRTE ALT AND HAD BEEN CLRED TO CLIMB AND MAINTAIN 3000 AS IS USUAL FOR THIS AREA. I READ BACK 3000' BUT SOMEHOW FIXATED ON 3500'. AS I WAS XING THROUGH 3100' APCH CALLED TFC AT 2 O'CLOCK AND 8 MI AT 3500' WHICH I SPOTTED AND RESPONDED WITH 'TALLYHO'. AS I WAS XING 3400' AND BEGINNING MY LEVEL OFF, APCH REQUESTED VERIFICATION OF ALT TO WHICH I RESPONDED 3500' AND THEY PROMPTLY INDICATED THAT I HAD BEEN CLRED TO 3000' AND HAD READ BACK 3000' AND SHOULD HAVE BEEN AT 3000. AS SOON AS THEY TOLD ME THAT I WAS CLRED TO 3000', I REALIZED MY ERROR, BUT NOT UNTIL THEN. I WOULD HAVE CONTINUED AT 3500' WITHOUT REALIZING IT IF THEY HAD NOT SAID ANYTHING. THE AIRPLANE I WAS FLYING HAD FUNCTIONAL MODE C BUT BY THE TIME THEY SAID ANYTHING THE OTHER ACFT HAD PASSED BEHIND ME BY ABOUT 1/2 MI AT MY ALT. I HAD THE OTHER ACFT IN SIGHT AND WAS WONDERING ABOUT THEM BRINGING US THAT CLOSE TOGETHER BUT ASSUMED THAT WE HAD LEGAL SEPARATION SINCE IT IS DIFFICULT TO JUDGE DISTANCE IN FLT ESPECIALLY WHEN THE OTHER ACFT'S TYPE IS UNKNOWN. NO ACTION WAS TAKEN AS NON WAS FELT NECESSARY. OF COURSE, I FAILED THE CHECKRIDE.

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.