First officer unfamiliar with altitude alerter in DH8 102 model does not notice altitude excursion.

Attributes
ACN	516980
Time
Date	200107
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : olm.vortac
State Reference	WA
Altitude	msl bound lower : 9200 msl bound upper : 10000
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Dash 8 Series Undifferentiated or Other Model
Flight Phase	descent : intermediate altitude
Route In Use	arrival star : n/s
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 175 flight time total : 13300 flight time type : 2000
ASRS Report	516980
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Resolutory Action	controller : issued new clearance
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Flying eug-sea. On this leg's initial takeoff from eug, aborted takeoff (per company procedure) because autofeather failed to arm. Returned to gate, swapped into incoming aircraft. Initial aircraft was dhc-8-202, swapped into dhc-8-102 model. Departed eug 1 hour late. Slightly harried descending into olm, I realized I did not have my approach plates for the arrival brief. On departure from eug, I had stuffed the plates in my flight bag. At about 11000 ft, 240 KIAS, 1500 FPM, cleared to 10000 ft, I told my first officer I was sticking my head in my flight bag to find the plates. I looked up shortly after to see us descending through 9200 ft. Advised ATC we were low. He told us to stay at 9000 ft. No shrill voices. Contributing factors: 1) first officer has been with the company 16 months. Most of his flying in the -202 model. On -202, altitude alerter has aural at 1000 ft prior and 300 ft off. -102 has light only. That set him up. 2) first officer is very competent. That set me up. 3) I deviated from my usual habit of only observing the leveloff and that prevented me from catching him.

Original NASA ASRS Text

Title: FO UNFAMILIAR WITH ALT ALERTER IN DH8 102 MODEL DOES NOT NOTICE ALT EXCURSION.

Narrative: FLYING EUG-SEA. ON THIS LEG'S INITIAL TKOF FROM EUG, ABORTED TKOF (PER COMPANY PROC) BECAUSE AUTOFEATHER FAILED TO ARM. RETURNED TO GATE, SWAPPED INTO INCOMING ACFT. INITIAL ACFT WAS DHC-8-202, SWAPPED INTO DHC-8-102 MODEL. DEPARTED EUG 1 HR LATE. SLIGHTLY HARRIED DSNDING INTO OLM, I REALIZED I DID NOT HAVE MY APCH PLATES FOR THE ARR BRIEF. ON DEP FROM EUG, I HAD STUFFED THE PLATES IN MY FLT BAG. AT ABOUT 11000 FT, 240 KIAS, 1500 FPM, CLRED TO 10000 FT, I TOLD MY FO I WAS STICKING MY HEAD IN MY FLT BAG TO FIND THE PLATES. I LOOKED UP SHORTLY AFTER TO SEE US DSNDING THROUGH 9200 FT. ADVISED ATC WE WERE LOW. HE TOLD US TO STAY AT 9000 FT. NO SHRILL VOICES. CONTRIBUTING FACTORS: 1) FO HAS BEEN WITH THE COMPANY 16 MONTHS. MOST OF HIS FLYING IN THE -202 MODEL. ON -202, ALT ALERTER HAS AURAL AT 1000 FT PRIOR AND 300 FT OFF. -102 HAS LIGHT ONLY. THAT SET HIM UP. 2) FO IS VERY COMPETENT. THAT SET ME UP. 3) I DEVIATED FROM MY USUAL HABIT OF ONLY OBSERVING THE LEVELOFF AND THAT PREVENTED ME FROM CATCHING HIM.

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.