Corp aircraft on arrival descends below assigned. Less than standard separation.

Attributes
ACN	194024
Time
Date	199111
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : pmd
State Reference	CA
Altitude	msl bound lower : 11300 msl bound upper : 12000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : msp
Operator	general aviation : corporate
Make Model Name	Light Transport
Flight Phase	cruise other descent other
Route In Use	arrival other enroute airway : edw
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 10000 flight time type : 2850
ASRS Report	194024
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : overshoot altitude deviation : crossing restriction not met conflict : airborne less severe non adherence : required legal separation non adherence : clearance
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 1000 vertical : 200
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

En route from palm springs, ca, (psp) to burbank, ca, (bur). Approaching palmdale VOR (pmd), we were cleared to 'cross palmdale VOR at 12000, descend to cross janny (LYNXX6 arrival at bur) intersection at 8000.' both the first officer and I heard the clearance correctly, but he put 8000 ft in the altitude alerter. Approximately 4 NM east of pmd, the controller asked us to 'confirm you are at 12000.' at that point we were passing 11300 in the descent. Then she called opposing traffic at our 12 O'clock. I initiated an immediate climb back towards 12000, and the traffic passed off to our left, approximately 200 ft below and 1000 ft to the left of our aircraft.

Original NASA ASRS Text

Title: CORP ACFT ON ARR DSNDS BELOW ASSIGNED. LTSS.

Narrative: ENRTE FROM PALM SPRINGS, CA, (PSP) TO BURBANK, CA, (BUR). APCHING PALMDALE VOR (PMD), WE WERE CLRED TO 'CROSS PALMDALE VOR AT 12000, DSND TO CROSS JANNY (LYNXX6 ARR AT BUR) INTXN AT 8000.' BOTH THE FO AND I HEARD THE CLRNC CORRECTLY, BUT HE PUT 8000 FT IN THE ALT ALERTER. APPROX 4 NM E OF PMD, THE CTLR ASKED US TO 'CONFIRM YOU ARE AT 12000.' AT THAT POINT WE WERE PASSING 11300 IN THE DSCNT. THEN SHE CALLED OPPOSING TFC AT OUR 12 O'CLOCK. I INITIATED AN IMMEDIATE CLB BACK TOWARDS 12000, AND THE TFC PASSED OFF TO OUR L, APPROX 200 FT BELOW AND 1000 FT TO THE L OF OUR ACFT.

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.