Altitude overshoot on arrival to phx, az.

Attributes
ACN	483380
Time
Date	200008
Day	Wed
Local Time Of Day	0601 To 1200
Place
State Reference	AZ
Altitude	msl bound lower : 8500 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : p50.tracon
Operator	general aviation : corporate
Make Model Name	IAI1124/1124A/Westwind
Operating Under FAR Part	Part 91
Navigation In Use	other vortac
Flight Phase	descent : approach
Route In Use	arrival star : drake
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 65 flight time total : 5250 flight time type : 1100
ASRS Report	483380
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
Events
Anomaly	altitude deviation : overshoot non adherence : clearance non adherence : published procedure
Independent Detector	aircraft equipment : altitude alert
Resolutory Action	controller : issued advisory flight crew : returned to assigned altitude
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On the drake arrival into phx we had been assigned on our descent 11000 ft, then 10000 ft, then 9000 ft. I evidently selected 'altitude select' as we were capturing altitude for 10000 ft and copilot was adjusting to new assigned altitude of 9000 ft. This caused my selection of 'altitude select' in the autoplt to be turned off and I failed to notice. While looking outside for the airport, my attention was caught by the alarm '300 ft below' bell and I immediately began ascending back up to 9000 ft. Controller asked us also to climb back to 9000 ft. Lesson learned!

Original NASA ASRS Text

Title: ALT OVERSHOOT ON ARR TO PHX, AZ.

Narrative: ON THE DRAKE ARR INTO PHX WE HAD BEEN ASSIGNED ON OUR DSCNT 11000 FT, THEN 10000 FT, THEN 9000 FT. I EVIDENTLY SELECTED 'ALT SELECT' AS WE WERE CAPTURING ALT FOR 10000 FT AND COPLT WAS ADJUSTING TO NEW ASSIGNED ALT OF 9000 FT. THIS CAUSED MY SELECTION OF 'ALT SELECT' IN THE AUTOPLT TO BE TURNED OFF AND I FAILED TO NOTICE. WHILE LOOKING OUTSIDE FOR THE ARPT, MY ATTN WAS CAUGHT BY THE ALARM '300 FT BELOW' BELL AND I IMMEDIATELY BEGAN ASCENDING BACK UP TO 9000 FT. CTLR ASKED US ALSO TO CLB BACK TO 9000 FT. LESSON LEARNED!

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.