Operating in dense fog, commuter taxies to wrong taxiway runway intersection.

Attributes
ACN	170562
Time
Date	199102
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : smf
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 2950 flight time type : 150
ASRS Report	170562
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : instrument
Experience	flight time last 90 days : 200 flight time total : 2000 flight time type : 900
ASRS Report	170254
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During taxi from the gate to 16R at smf, the fog was quite dense and we were required to inform sacramento ground when we turned onto each taxiway. While taxiing we went through the normal company checklists. As a crew member I was dividing my attention between taxiway, checklist, and the actual item being addressed. We informed the ground controller when we turned on each taxiway as per his instructions. Looking up from the checklist I saw the runway sign indicating we were at runway 16R. I called the tower ready for departure 16R. He replied taxi into position, report in position. At this time the captain indicated that she didn't believe we were at the beginning of 16R, and instructed me to ask tower for back-taxi on runway 16R. I asked the tower for a back-taxi clearance. He asked us, 'where are you?', or something to that effect indicating he expected us to be at the beginning of 16R. So did we, but we didn't see an intersection sign while taxiing. He said to back-taxi 16R, then he exclaimed, 'I hope you understand the gravity of the situation.' we paused trying to figure out what he meant by this. We didn't break any regulations that we could think of. We just hadn't taxied to the beginning of 16R, though at the time we thought we had. He had cleared us onto the runway, but we held short as the captain asked me to get a back-taxi clearance, because she now realized we were not at the beginning of 16R. He gave us the clearance, we back-taxied and were subsequently cleared for takeoff. As he handed us off to departure, I asked if there was going to be a problem, and he replied, 'I don't know yet.' the problems contributing to our misjudging our position along 16R were that the fog was denser in some places than others. Our being busy with checklists, and the lack of or inability to see an intersection sign. Also the fact that there was a sign indicating 16R. Supplemental information from acn 170254: I was familiar with this airport and with the taxi instructions given, so I elected not to take out the airport diagram map.

Original NASA ASRS Text

Title: OPERATING IN DENSE FOG, COMMUTER TAXIES TO WRONG TXWY RWY INTERSECTION.

Narrative: DURING TAXI FROM THE GATE TO 16R AT SMF, THE FOG WAS QUITE DENSE AND WE WERE REQUIRED TO INFORM SACRAMENTO GND WHEN WE TURNED ONTO EACH TXWY. WHILE TAXIING WE WENT THROUGH THE NORMAL COMPANY CHKLISTS. AS A CREW MEMBER I WAS DIVIDING MY ATTN BTWN TXWY, CHKLIST, AND THE ACTUAL ITEM BEING ADDRESSED. WE INFORMED THE GND CTLR WHEN WE TURNED ON EACH TXWY AS PER HIS INSTRUCTIONS. LOOKING UP FROM THE CHKLIST I SAW THE RWY SIGN INDICATING WE WERE AT RWY 16R. I CALLED THE TWR READY FOR DEP 16R. HE REPLIED TAXI INTO POS, RPT IN POS. AT THIS TIME THE CAPT INDICATED THAT SHE DIDN'T BELIEVE WE WERE AT THE BEGINNING OF 16R, AND INSTRUCTED ME TO ASK TWR FOR BACK-TAXI ON RWY 16R. I ASKED THE TWR FOR A BACK-TAXI CLRNC. HE ASKED US, 'WHERE ARE YOU?', OR SOMETHING TO THAT EFFECT INDICATING HE EXPECTED US TO BE AT THE BEGINNING OF 16R. SO DID WE, BUT WE DIDN'T SEE AN INTXN SIGN WHILE TAXIING. HE SAID TO BACK-TAXI 16R, THEN HE EXCLAIMED, 'I HOPE YOU UNDERSTAND THE GRAVITY OF THE SITUATION.' WE PAUSED TRYING TO FIGURE OUT WHAT HE MEANT BY THIS. WE DIDN'T BREAK ANY REGS THAT WE COULD THINK OF. WE JUST HADN'T TAXIED TO THE BEGINNING OF 16R, THOUGH AT THE TIME WE THOUGHT WE HAD. HE HAD CLRED US ONTO THE RWY, BUT WE HELD SHORT AS THE CAPT ASKED ME TO GET A BACK-TAXI CLRNC, BECAUSE SHE NOW REALIZED WE WERE NOT AT THE BEGINNING OF 16R. HE GAVE US THE CLRNC, WE BACK-TAXIED AND WERE SUBSEQUENTLY CLRED FOR TKOF. AS HE HANDED US OFF TO DEP, I ASKED IF THERE WAS GOING TO BE A PROB, AND HE REPLIED, 'I DON'T KNOW YET.' THE PROBS CONTRIBUTING TO OUR MISJUDGING OUR POS ALONG 16R WERE THAT THE FOG WAS DENSER IN SOME PLACES THAN OTHERS. OUR BEING BUSY WITH CHKLISTS, AND THE LACK OF OR INABILITY TO SEE AN INTXN SIGN. ALSO THE FACT THAT THERE WAS A SIGN INDICATING 16R. SUPPLEMENTAL INFO FROM ACN 170254: I WAS FAMILIAR WITH THIS ARPT AND WITH THE TAXI INSTRUCTIONS GIVEN, SO I ELECTED NOT TO TAKE OUT THE ARPT DIAGRAM MAP.

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.