Narrative:

During vector to final and descending below overcast layer; we did not level off with autopilot engaged. We disconnected autopilot and proceeded in VFR to join ILS. Controller gave us a low altitude alert as we were correcting and we thanked them for being alert. This was the first trip for pilot flying using this particular avionics package. It takes a little longer to correct things when you are not familiar with them as you question whether you are interpreting information correctly. FMS and autopilot systems work similarly; but have different ways and locations for annunciators. It's easy to think you have set something properly and then be forced to correct. This rapid correction can also prevent you from going back to see if something was 'set' or 'captured' or failed to 'engage' or 'capture.'

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Original NASA ASRS Text

Title: A BE 350 Pilot operating with a new avionics package had an altitude deviation after the autopilot did not capture the selected altitude during descent for approach. Confusion about FMS and Autopilot functions and control locations contributed.

Narrative: During vector to final and descending below overcast layer; we did not level off with autopilot engaged. We disconnected autopilot and proceeded in VFR to join ILS. Controller gave us a low altitude alert as we were correcting and we thanked them for being alert. This was the first trip for pilot flying using this particular avionics package. It takes a little longer to correct things when you are not familiar with them as you question whether you are interpreting information correctly. FMS and autopilot systems work similarly; but have different ways and locations for annunciators. It's easy to think you have set something properly and then be forced to correct. This rapid correction can also prevent you from going back to see if something was 'set' or 'captured' or failed to 'engage' or 'capture.'

Data retrieved from NASA's ASRS site as of July 2013 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.