Narrative:

Upon climbing out from goodland, ks, I received an amendment to my clearance. I was filed from goodland direct centennial at 12000 ft. The amendment was to fly V108 to hugo VOR, then the quail 3 arrival to centennial maintain 8000 ft. I read back V108 to hugo quail 3 arrival centennial, I did not hear or read back maintain 8000 ft. The controller told readback correct. As I climbed through 7900 ft, the controller said radar contact maintain 8000 ft. I read back maintain 8000 ft and pushed the nose over. Because there was a patient on board and it was turbulent, I did not stop the climb in an overly aggressive manner. Due to turbulence, it took an abnormal amount of power reduction to arrest the climb, possible mountain wave or windshear. The climb was stopped at 8500 ft and at that time controller asked altitude. I stated 8500 ft for 8000 ft. The altitude deviation was a result of being under the understanding that I was cleared to 12000 ft and because I was told that the readback was correct.

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Original NASA ASRS Text

Title: AMBULANCE FLT ON IFR CLRNC TO APA CLBING TO 12000 FT. RECEIVED AMENDED CLRNC WITHOUT ALT STATED.

Narrative: UPON CLBING OUT FROM GOODLAND, KS, I RECEIVED AN AMENDMENT TO MY CLRNC. I WAS FILED FROM GOODLAND DIRECT CENTENNIAL AT 12000 FT. THE AMENDMENT WAS TO FLY V108 TO HUGO VOR, THEN THE QUAIL 3 ARR TO CENTENNIAL MAINTAIN 8000 FT. I READ BACK V108 TO HUGO QUAIL 3 ARR CENTENNIAL, I DID NOT HEAR OR READ BACK MAINTAIN 8000 FT. THE CTLR TOLD READBACK CORRECT. AS I CLBED THROUGH 7900 FT, THE CTLR SAID RADAR CONTACT MAINTAIN 8000 FT. I READ BACK MAINTAIN 8000 FT AND PUSHED THE NOSE OVER. BECAUSE THERE WAS A PATIENT ON BOARD AND IT WAS TURBULENT, I DID NOT STOP THE CLB IN AN OVERLY AGGRESSIVE MANNER. DUE TO TURB, IT TOOK AN ABNORMAL AMOUNT OF PWR REDUCTION TO ARREST THE CLB, POSSIBLE MOUNTAIN WAVE OR WINDSHEAR. THE CLB WAS STOPPED AT 8500 FT AND AT THAT TIME CTLR ASKED ALT. I STATED 8500 FT FOR 8000 FT. THE ALTDEV WAS A RESULT OF BEING UNDER THE UNDERSTANDING THAT I WAS CLRED TO 12000 FT AND BECAUSE I WAS TOLD THAT THE READBACK WAS CORRECT.

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.