GPWS warning on approach to san while at MVA.

Attributes
ACN	303905
Time
Date	199505
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : san
State Reference	CA
Altitude	msl bound lower : 5000 msl bound upper : 5700
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : san
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : flight engineer pilot : instrument
Experience	flight time last 90 days : 200 flight time total : 12000 flight time type : 1900
ASRS Report	303905
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Being radar vectored to final approach due to WX in area. At approximately 20.8 DME off of san localizer DME runway 27 on base to final leg (heading 210 degrees at 5000 ft) for the localizer, the GPWS terrain warning, followed by pull up, came on. Immediately climbed to 5700 ft when the warning stopped. Notified approach of terrain warning and was advised that MVA in our area was 5000 ft. We were told that a hill of 3600 ft to the south of us might have triggered our GPWS. We returned back to 5000 ft. Rest of flight was uneventful. Did not have chance to look at radar altimeter for any altitude information. Did not want to question GPWS activation. Followed our company's procedures. I was only able to glance at DME while in the climb.

Original NASA ASRS Text

Title: GPWS WARNING ON APCH TO SAN WHILE AT MVA.

Narrative: BEING RADAR VECTORED TO FINAL APCH DUE TO WX IN AREA. AT APPROX 20.8 DME OFF OF SAN LOC DME RWY 27 ON BASE TO FINAL LEG (HDG 210 DEGS AT 5000 FT) FOR THE LOC, THE GPWS TERRAIN WARNING, FOLLOWED BY PULL UP, CAME ON. IMMEDIATELY CLBED TO 5700 FT WHEN THE WARNING STOPPED. NOTIFIED APCH OF TERRAIN WARNING AND WAS ADVISED THAT MVA IN OUR AREA WAS 5000 FT. WE WERE TOLD THAT A HILL OF 3600 FT TO THE S OF US MIGHT HAVE TRIGGERED OUR GPWS. WE RETURNED BACK TO 5000 FT. REST OF FLT WAS UNEVENTFUL. DID NOT HAVE CHANCE TO LOOK AT RADAR ALTIMETER FOR ANY ALT INFO. DID NOT WANT TO QUESTION GPWS ACTIVATION. FOLLOWED OUR COMPANY'S PROCS. I WAS ONLY ABLE TO GLANCE AT DME WHILE IN THE CLB.

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.