Narrative:

I was pilot monitoring as we were being vectored on arrival. The first officer had turned off the autopilot. I went heads down to program the FMS and pull up a message on ACARS. Shortly thereafter I heard the altitude alert sound and the first officer was correcting altitude to return to our assigned altitude. He said he had looked at something else and didn't notice he was losing altitude. We immediately returned to altitude and no mention or query was made by ATC. This aircraft had a configuration where the FMS was full aft on the center pedestal which makes it impossible to program the FMS and also keep an eye on the pfd/mfd. I didn't notice the altitude loss until the horn went off. I debriefed the first officer regarding obligations while hand flying.

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Original NASA ASRS Text

Title: EMB-145 Captain reports an altitude deviation by the First Officer who is hand flying on vectors for approach. The Captains attention was diverted by FMC work which is physically located on aft end of the center pedestal.

Narrative: I was Pilot Monitoring as we were being vectored on arrival. The First Officer had turned off the autopilot. I went heads down to program the FMS and pull up a message on ACARS. Shortly thereafter I heard the altitude alert sound and the First Officer was correcting altitude to return to our assigned altitude. He said he had looked at something else and didn't notice he was losing altitude. We immediately returned to altitude and no mention or query was made by ATC. This aircraft had a configuration where the FMS was full aft on the center pedestal which makes it impossible to program the FMS and also keep an eye on the PFD/MFD. I didn't notice the altitude loss until the horn went off. I debriefed the First Officer regarding obligations while hand flying.

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.