Narrative:

As we took of on runway 24 in teb; departure control cleared us to 6;000 ft. 300 ft before leveling ATC gave us a fix and a radial that was not on our flight plan. As the other pilot verified the new FMS input was correct; the autopilot did not capture the altitude. We both rapidly detected the problem and the captain corrected immediately within less that 250 ft. ATC then confirmed which altitude we were climbing to after we were back at 6;000 ft and again 30 seconds later. It seemed like ATC was reading a different altitude than we were at. Things that could have been better: ATC gave us a fix thinking we knew its spelling - as we verified the spelling ATC got aggravated and was not helping at all. It also happened just at altitude capture when the pilot flying was looking away from his pfd.

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Original NASA ASRS Text

Title: A P180 departing from TEB failed to stop the climb at their cleared altitude. Distractions due to programming a previous airways clearance that was not a part of their cleared route contributed to the Flight Crew's failure to recognize the impending deviation in time.

Narrative: As we took of on Runway 24 in TEB; Departure Control cleared us to 6;000 FT. 300 FT before leveling ATC gave us a fix and a radial that was not on our flight plan. As the other pilot verified the new FMS input was correct; the autopilot did not capture the altitude. We both rapidly detected the problem and the Captain corrected immediately within less that 250 FT. ATC then confirmed which altitude we were climbing to after we were back at 6;000 FT and again 30 seconds later. It seemed like ATC was reading a different altitude than we were at. Things that could have been better: ATC gave us a fix thinking we knew its spelling - as we verified the spelling ATC got aggravated and was not helping at all. It also happened just at altitude capture when the pilot flying was looking away from his PFD.

Data retrieved from NASA's ASRS site as of April 2012 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.