Reporter's aircraft GPWS activated in an area of known high terrain.

Attributes
ACN	437732
Time
Date	199905
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : ffu.vortac
State Reference	UT
Altitude	msl single value : 9000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : s56.tracon
Operator	common carrier : air carrier
Make Model Name	MD-90 Series (DC-9-90) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 34r other
Flight Phase	descent : approach
Route In Use	approach : instrument precision
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : commercial pilot : multi engine pilot : instrument pilot : flight engineer
Experience	fss specialist : 1 flight time last 90 days : 200 flight time total : 3000 flight time type : 300
ASRS Report	437732
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : company policies non adherence : published procedure other anomaly other
Independent Detector	aircraft equipment : gpws other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	other
Supplementary
Problem Areas	FAA Chart Or Publication Aircraft ATC Human Performance Flight Crew Human Performance
Primary Problem	Aircraft

Narrative:

Coming from the west for ILS runway 34R at slc, sounded like it could have been a controller in training. Almost directly over ffu VOR, headed for 'plage' fix on ILS runway 34R, I was cleared to 9000 ft MSL. Captain remarked how he'd never been so low 30 DME out. Shortly after descent initiated, got 'terrain, terrain' warning, followed immediately by 'pull up! Pull up!' from GPWS. I hit toga power and climbed to about 10300 ft. Captain notified ATC and they had us level at 10000 ft. Cleared for ILS runway 34R with uneventful landing. I'm not sure of the logic descending us so early. Approach plate says 10500 ft over ffu and 10500 ft (9000 ft when authority/authorized by ATC) at plage. I can't tell you how uncomfortable it is to hear 'pull up' in clouds with mountains in proximity. I recommend not descending aircraft below 10500 ft until plage intersection. Callback conversation with reporter revealed the following information: talking to slc TRACON revealed that they have received many complaints about aircraft GPWS being activated in the same general area while being vectored to the slc final runway 34R. Between the ffu VOR and plage, controllers have the option to use 9000 ft. This is depicted on the charts. ZLC has had the terrain clearance altitudes checked many times as a result of these complaints, and have found nothing wrong. The MVA in this area varies between 8000-9000 ft. The maximum ht of the terrain on either side of the final approach course in the vicinity of plage is 6682 ft on the east side and 6824 ft on the west side. One reason for so many GPWS activations is the ridge line just inside of plage. In this area, we have a rapidly raising terrain to a point 2000 ft above the floor of the valley. Callback to reporter revealed that his aircraft was equipped with the older GPWS. He believes that his GPWS was activated by rapidly raising terrain and a high rate of descent. Reporter stated the scary part of this was they were in the clouds when their GPWS went off.

Original NASA ASRS Text

Title: RPTR'S ACFT GPWS ACTIVATED IN AN AREA OF KNOWN HIGH TERRAIN.

Narrative: COMING FROM THE W FOR ILS RWY 34R AT SLC, SOUNDED LIKE IT COULD HAVE BEEN A CTLR IN TRAINING. ALMOST DIRECTLY OVER FFU VOR, HEADED FOR 'PLAGE' FIX ON ILS RWY 34R, I WAS CLRED TO 9000 FT MSL. CAPT REMARKED HOW HE'D NEVER BEEN SO LOW 30 DME OUT. SHORTLY AFTER DSCNT INITIATED, GOT 'TERRAIN, TERRAIN' WARNING, FOLLOWED IMMEDIATELY BY 'PULL UP! PULL UP!' FROM GPWS. I HIT TOGA PWR AND CLBED TO ABOUT 10300 FT. CAPT NOTIFIED ATC AND THEY HAD US LEVEL AT 10000 FT. CLRED FOR ILS RWY 34R WITH UNEVENTFUL LNDG. I'M NOT SURE OF THE LOGIC DSNDING US SO EARLY. APCH PLATE SAYS 10500 FT OVER FFU AND 10500 FT (9000 FT WHEN AUTH BY ATC) AT PLAGE. I CAN'T TELL YOU HOW UNCOMFORTABLE IT IS TO HEAR 'PULL UP' IN CLOUDS WITH MOUNTAINS IN PROX. I RECOMMEND NOT DSNDING ACFT BELOW 10500 FT UNTIL PLAGE INTXN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: TALKING TO SLC TRACON REVEALED THAT THEY HAVE RECEIVED MANY COMPLAINTS ABOUT ACFT GPWS BEING ACTIVATED IN THE SAME GENERAL AREA WHILE BEING VECTORED TO THE SLC FINAL RWY 34R. BTWN THE FFU VOR AND PLAGE, CTLRS HAVE THE OPTION TO USE 9000 FT. THIS IS DEPICTED ON THE CHARTS. ZLC HAS HAD THE TERRAIN CLRNC ALTS CHKED MANY TIMES AS A RESULT OF THESE COMPLAINTS, AND HAVE FOUND NOTHING WRONG. THE MVA IN THIS AREA VARIES BTWN 8000-9000 FT. THE MAX HT OF THE TERRAIN ON EITHER SIDE OF THE FINAL APCH COURSE IN THE VICINITY OF PLAGE IS 6682 FT ON THE E SIDE AND 6824 FT ON THE W SIDE. ONE REASON FOR SO MANY GPWS ACTIVATIONS IS THE RIDGE LINE JUST INSIDE OF PLAGE. IN THIS AREA, WE HAVE A RAPIDLY RAISING TERRAIN TO A POINT 2000 FT ABOVE THE FLOOR OF THE VALLEY. CALLBACK TO RPTR REVEALED THAT HIS ACFT WAS EQUIPPED WITH THE OLDER GPWS. HE BELIEVES THAT HIS GPWS WAS ACTIVATED BY RAPIDLY RAISING TERRAIN AND A HIGH RATE OF DSCNT. RPTR STATED THE SCARY PART OF THIS WAS THEY WERE IN THE CLOUDS WHEN THEIR GPWS WENT OFF.

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.