A320 crew got a GPWS 'too low terrain' warning at tus runway 11L.

Attributes
ACN	514138
Time
Date	200106
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : tus.airport
State Reference	AZ
Altitude	msl bound lower : 6200 msl bound upper : 6800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : u90.tracon tracon : d10.tracon
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 11l
Flight Phase	descent : approach
Route In Use	approach : visual approach : instrument precision
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : instrument pilot : atp
Experience	flight time last 90 days : 250 flight time total : 10400 flight time type : 1300
ASRS Report	514138
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment : gpws other flight crewa other flight crewb
Resolutory Action	flight crew : took evasive action other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Arriving into tus on a visual clearance. Heading about 110 degrees direct to wason intersection for the visual (ILS backup) to runway 11L. Descending to 6000 ft MSL at 250 KIAS, clean confign and about 1200-1400 FPM rate of descent, slightly below/on the ILS GS. At 6200 ft MSL and about 2-3 NM prior to wason in got a GPWS, 'too low terrain.' hill at about that position at 4687 ft. Disconnected the autoplt and began a climb. GPWS quit at 6800 ft MSL. No injuries in the cabin. Continued to a normal landing at tucson. Elected to following GPWS recovery as taught because I was not 100% sure it shouldn't be followed even though day, VFR with 30 NM visibility. We do this training in the simulator and I reacted as taught, that's good. I believe that the GPWS went off inappropriately and its continuing to 6800 ft MSL bolsters that opinion. Submitted a safety report to the company and a call to our pilot organization safety hotline. Minimum altitude to wason is 6000 ft MSL and that is what I was descending to.

Original NASA ASRS Text

Title: A320 CREW GOT A GPWS 'TOO LOW TERRAIN' WARNING AT TUS RWY 11L.

Narrative: ARRIVING INTO TUS ON A VISUAL CLRNC. HEADING ABOUT 110 DEGS DIRECT TO WASON INTXN FOR THE VISUAL (ILS BACKUP) TO RWY 11L. DSNDING TO 6000 FT MSL AT 250 KIAS, CLEAN CONFIGN AND ABOUT 1200-1400 FPM RATE OF DSCNT, SLIGHTLY BELOW/ON THE ILS GS. AT 6200 FT MSL AND ABOUT 2-3 NM PRIOR TO WASON IN GOT A GPWS, 'TOO LOW TERRAIN.' HILL AT ABOUT THAT POS AT 4687 FT. DISCONNECTED THE AUTOPLT AND BEGAN A CLB. GPWS QUIT AT 6800 FT MSL. NO INJURIES IN THE CABIN. CONTINUED TO A NORMAL LNDG AT TUCSON. ELECTED TO FOLLOWING GPWS RECOVERY AS TAUGHT BECAUSE I WAS NOT 100% SURE IT SHOULDN'T BE FOLLOWED EVEN THOUGH DAY, VFR WITH 30 NM VISIBILITY. WE DO THIS TRAINING IN THE SIMULATOR AND I REACTED AS TAUGHT, THAT'S GOOD. I BELIEVE THAT THE GPWS WENT OFF INAPPROPRIATELY AND ITS CONTINUING TO 6800 FT MSL BOLSTERS THAT OPINION. SUBMITTED A SAFETY RPT TO THE COMPANY AND A CALL TO OUR PLT ORGANIZATION SAFETY HOTLINE. MINIMUM ALT TO WASON IS 6000 FT MSL AND THAT IS WHAT I WAS DSNDING TO.

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.