Commuter descends below assigned altitude.

Attributes
ACN	303900
Time
Date	199505
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : oxr
State Reference	CA
Altitude	msl bound lower : 3400 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ntd
Operator	common carrier : air carrier
Make Model Name	Jetstream 32
Operating Under FAR Part	Part 135
Flight Phase	cruise other descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : cfi pilot : atp pilot : commercial
Experience	flight time last 90 days : 150 flight time total : 5500 flight time type : 1200
ASRS Report	303900
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	none taken : insufficient time
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Tracking localizer 10 mi at 4000 ft, expecting visual clearance after calling traffic in sight ahead 2 mi, 3500 ft. Numerous other traffic in vicinity of cma airport. Captain (PNF), first officer (PF). Captain looking for traffic, first officer reduced power to slow aircraft and was looking for traffic instead of flying. Lost 600 ft to 3400 ft before cleared. No conflict occurred, as we were passed traffic.

Original NASA ASRS Text

Title: COMMUTER DSNDS BELOW ASSIGNED ALT.

Narrative: TRACKING LOC 10 MI AT 4000 FT, EXPECTING VISUAL CLRNC AFTER CALLING TFC IN SIGHT AHEAD 2 MI, 3500 FT. NUMEROUS OTHER TFC IN VICINITY OF CMA ARPT. CAPT (PNF), FO (PF). CAPT LOOKING FOR TFC, FO REDUCED PWR TO SLOW ACFT AND WAS LOOKING FOR TFC INSTEAD OF FLYING. LOST 600 FT TO 3400 FT BEFORE CLRED. NO CONFLICT OCCURRED, AS WE WERE PASSED TFC.

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.