A B767 crew making a visual approach to slc descended below crossing restr.

Attributes
ACN	520956
Time
Date	200108
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : s56.tracon
State Reference	MT
Altitude	msl bound lower : 6900 msl bound upper : 7500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : s56.tracon tracon : dca.tracon
Operator	common carrier : air carrier
Make Model Name	B767 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 16l
Flight Phase	descent : approach
Route In Use	approach : instrument precision arrival star : bearr.bearry
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : instrument pilot : multi engine pilot : atp
Experience	flight time last 90 days : 165 flight time total : 16500 flight time type : 2750
ASRS Report	520956
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot altitude deviation : crossing restriction not met non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : eicas message other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On vectors for a visual approach to runway 16L (runway threshold displacement of 1920 ft) men and equipment working on closed portion, 10000+ ft available for landing, a 'very' dim or weak plasi on the left side of the runway. GS inoperative. Excellent ceiling and visibility, we called runway in sight at approximately irron. While on vectors for a visual approach the controller cleared us to 8000 ft and further cleared us visual approach upon passing 9000 ft. Lined up on final (localizer captured). The approach controller came back and cleared us visual approach runway 16L to cross lgoon at or above 7500 ft. I set 7500 ft in the altitude window. At lgoon (via the EFIS map) reset the altitude window to the minimum altitude (10000 ft) and set the vertical speed to 700/800 FPM. Continued configuring the flaps. Upon looking outside (runway -- weak plasi) we appeared to be low. No GS available (displaced threshold). Checked our altitude at 6900 ft and the map position just passing lgoon (I believe we had a map shift -- +/-3 mi). Questioning what was going, I verified our position via localizer DME. We were just passing lgoon (12.3 localizer DME). The controller called and asked what altitude we had understood to cross lgoon (7500 ft or above). I explained that we understood that we were to cross lgoon at or above 7500 ft and further explained that we had had a map shift. He explained the importance of the crossing altitude (7500 ft) and cautioned about the altitude for future visual approach to runway 16L. We apologized and thanked the controller, went to tower for our landing clearance. I believe that this situation could have been prevented if we had verified (crosschecked) what we had thought to be lgoon (map position) with raw data (localizer DME). It would have shown the error (discrepancy -- map shift). It was a busy cockpit but that would have idented the map shift and we could have worked it out from there. It's never too busy to xchk raw data. It has also made me think twice about EFIS generated navigation data. Verify, even in very VFR conditions.

Original NASA ASRS Text

Title: A B767 CREW MAKING A VISUAL APCH TO SLC DSNDED BELOW XING RESTR.

Narrative: ON VECTORS FOR A VISUAL APCH TO RWY 16L (RWY THRESHOLD DISPLACEMENT OF 1920 FT) MEN AND EQUIP WORKING ON CLOSED PORTION, 10000+ FT AVAILABLE FOR LNDG, A 'VERY' DIM OR WEAK PLASI ON THE L SIDE OF THE RWY. GS INOP. EXCELLENT CEILING AND VISIBILITY, WE CALLED RWY IN SIGHT AT APPROX IRRON. WHILE ON VECTORS FOR A VISUAL APCH THE CTLR CLRED US TO 8000 FT AND FURTHER CLRED US VISUAL APCH UPON PASSING 9000 FT. LINED UP ON FINAL (LOC CAPTURED). THE APCH CTLR CAME BACK AND CLRED US VISUAL APCH RWY 16L TO CROSS LGOON AT OR ABOVE 7500 FT. I SET 7500 FT IN THE ALT WINDOW. AT LGOON (VIA THE EFIS MAP) RESET THE ALT WINDOW TO THE MINIMUM ALT (10000 FT) AND SET THE VERT SPD TO 700/800 FPM. CONTINUED CONFIGURING THE FLAPS. UPON LOOKING OUTSIDE (RWY -- WEAK PLASI) WE APPEARED TO BE LOW. NO GS AVAILABLE (DISPLACED THRESHOLD). CHKED OUR ALT AT 6900 FT AND THE MAP POS JUST PASSING LGOON (I BELIEVE WE HAD A MAP SHIFT -- +/-3 MI). QUESTIONING WHAT WAS GOING, I VERIFIED OUR POS VIA LOC DME. WE WERE JUST PASSING LGOON (12.3 LOC DME). THE CTLR CALLED AND ASKED WHAT ALT WE HAD UNDERSTOOD TO CROSS LGOON (7500 FT OR ABOVE). I EXPLAINED THAT WE UNDERSTOOD THAT WE WERE TO CROSS LGOON AT OR ABOVE 7500 FT AND FURTHER EXPLAINED THAT WE HAD HAD A MAP SHIFT. HE EXPLAINED THE IMPORTANCE OF THE XING ALT (7500 FT) AND CAUTIONED ABOUT THE ALT FOR FUTURE VISUAL APCH TO RWY 16L. WE APOLOGIZED AND THANKED THE CTLR, WENT TO TWR FOR OUR LNDG CLRNC. I BELIEVE THAT THIS SIT COULD HAVE BEEN PREVENTED IF WE HAD VERIFIED (XCHKED) WHAT WE HAD THOUGHT TO BE LGOON (MAP POS) WITH RAW DATA (LOC DME). IT WOULD HAVE SHOWN THE ERROR (DISCREPANCY -- MAP SHIFT). IT WAS A BUSY COCKPIT BUT THAT WOULD HAVE IDENTED THE MAP SHIFT AND WE COULD HAVE WORKED IT OUT FROM THERE. IT'S NEVER TOO BUSY TO XCHK RAW DATA. IT HAS ALSO MADE ME THINK TWICE ABOUT EFIS GENERATED NAV DATA. VERIFY, EVEN IN VERY VFR CONDITIONS.

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.