B737-700 flight crew reported receiving a false GPWS terrain warning on approach into smf.

Attributes
ACN	1523694
Time
Date	201803
Place
Locale Reference	SMF.Airport
State Reference	CA
Aircraft 1
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	Landing
Flight Plan	IFR
Component
Aircraft Component	GPWS
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 371
Person 2
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 425
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

We were on stabilized final; on glide path; on VASI; configured to land. At about 600-700 feet we got a 'too low terrain' verbal alert. We were confused as the terrain was flat; we were very stable on glide path; and light wind. We saw no reason whatsoever for the alert. We went around. We put in the RNAV approach for back up on subsequent visual approach. Maintenance said they would run some tests on the system and look for history. Very odd.

Original NASA ASRS Text

Title: B737-700 flight crew reported receiving a false GPWS terrain warning on approach into SMF.

Narrative: We were on stabilized final; on glide path; on VASI; configured to land. At about 600-700 feet we got a 'Too Low Terrain' verbal alert. We were confused as the terrain was flat; we were very stable on glide path; and light wind. We saw no reason whatsoever for the alert. We went around. We put in the RNAV Approach for back up on subsequent visual approach. Maintenance said they would run some tests on the system and look for history. Very odd.

Data retrieved from NASA's ASRS site 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.