Narrative:

We were on an IFR flight plan from cyyz to rdu. Copilot was flying and I, the captain, was involved with calling customs to update our arrival time to rdu and dealing with our passenger. We were at FL290 and were told to descend to FL270. Copilot started descent on the autoplt. The autoplt failed to capture the altitude and copilot failed to see the deviation. Action was taken by me, the captain, to correct the deviation as center asked our altitude. Copilot responded, correcting to FL270. Less than 1000 ft deviation occurred. I observed our TCASII and saw no visual problems. I then asked if we had a problem with center and they advised, 'we are reviewing it now.'

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Original NASA ASRS Text

Title: A FALCON 10 CAPT RPTED AN ALT DEV IN ZOB'S AIRSPACE.

Narrative: WE WERE ON AN IFR FLT PLAN FROM CYYZ TO RDU. COPLT WAS FLYING AND I, THE CAPT, WAS INVOLVED WITH CALLING CUSTOMS TO UPDATE OUR ARR TIME TO RDU AND DEALING WITH OUR PAX. WE WERE AT FL290 AND WERE TOLD TO DSND TO FL270. COPLT STARTED DSCNT ON THE AUTOPLT. THE AUTOPLT FAILED TO CAPTURE THE ALT AND COPLT FAILED TO SEE THE DEV. ACTION WAS TAKEN BY ME, THE CAPT, TO CORRECT THE DEV AS CTR ASKED OUR ALT. COPLT RESPONDED, CORRECTING TO FL270. LESS THAN 1000 FT DEV OCCURRED. I OBSERVED OUR TCASII AND SAW NO VISUAL PROBLEMS. I THEN ASKED IF WE HAD A PROB WITH CTR AND THEY ADVISED, 'WE ARE REVIEWING IT NOW.'

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.