Altitude deviation excursion from clearance altitude on vectors to sjc.

Attributes
ACN	197649
Time
Date	199112
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : sjc
State Reference	CA
Altitude	msl bound lower : 3000 msl bound upper : 3300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : oak
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other descent other
Route In Use	approach : visual enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 6500 flight time type : 1600
ASRS Report	197649
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Miss Distance	vertical : 600
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

On radar vectors, downwind for runway 12R sjc, approach control issued TA for aircraft at 11 O'clock and 6 mi. Picked up traffic on TCASII indicating 600 ft below us. Never sighted traffic visually. Traffic then set off TCASII alert (TA). Shortly thereafter, TCASII issued RA indication of pull up as target entered our zone. First officer pulled up with my concurrence and we exceeded our assigned altitude +200 ft. Shortly after this TCASII gave all clear, and we descended back to assigned altitude.

Original NASA ASRS Text

Title: ALTDEV EXCURSION FROM CLRNC ALT ON VECTORS TO SJC.

Narrative: ON RADAR VECTORS, DOWNWIND FOR RWY 12R SJC, APCH CTL ISSUED TA FOR ACFT AT 11 O'CLOCK AND 6 MI. PICKED UP TFC ON TCASII INDICATING 600 FT BELOW US. NEVER SIGHTED TFC VISUALLY. TFC THEN SET OFF TCASII ALERT (TA). SHORTLY THEREAFTER, TCASII ISSUED RA INDICATION OF PULL UP AS TARGET ENTERED OUR ZONE. FO PULLED UP WITH MY CONCURRENCE AND WE EXCEEDED OUR ASSIGNED ALT +200 FT. SHORTLY AFTER THIS TCASII GAVE ALL CLR, AND WE DSNDED BACK TO ASSIGNED ALT.

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.