Aircraft taxies during snowstorm to line up for takeoff on taxiway next to runway.

Attributes
ACN	325530
Time
Date	199601
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : den
State Reference	CO
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	Marginal
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 12000 flight time type : 1500
ASRS Report	325530
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 16000 flight time type : 650
ASRS Report	325690
Events
Anomaly	non adherence : clearance other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : became reoriented other
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation other

Narrative:

Air carrier xx den-ewr, cleared to taxi from spot Y, den ramp to runway 34 via taxiway G. Snow was blowing over taxiway markings runway numbers. At the intersection of taxiway G, taxiway fox 1, flight held for clearance onto runway 34. Tower cleared air carrier xx into position and hold. Aircraft was lined, mistakenly on taxiway F. Tower commented, 'it looked like xx was facing north on taxiway F.' as the controller was responding, the pilots realized they were still on taxiway F. Air carrier xx was then cleared to taxi to runway 34. Takeoff and flight was made without further incident. Blowing and drifting snow along with darkness contributed to the mistake. There was never any engine run-up, or brake release before mistake was discovered. Mistake was discovered by pilots even before remarks were made by den tower. Supplemental information from acn 325690: this problem arose mostly because of blowing and drifting snow obscuring taxiway markers and lights.

Original NASA ASRS Text

Title: ACFT TAXIES DURING SNOWSTORM TO LINE UP FOR TKOF ON TXWY NEXT TO RWY.

Narrative: ACR XX DEN-EWR, CLRED TO TAXI FROM SPOT Y, DEN RAMP TO RWY 34 VIA TXWY G. SNOW WAS BLOWING OVER TXWY MARKINGS RWY NUMBERS. AT THE INTXN OF TXWY G, TXWY FOX 1, FLT HELD FOR CLRNC ONTO RWY 34. TWR CLRED ACR XX INTO POS AND HOLD. ACFT WAS LINED, MISTAKENLY ON TXWY F. TWR COMMENTED, 'IT LOOKED LIKE XX WAS FACING N ON TXWY F.' AS THE CTLR WAS RESPONDING, THE PLTS REALIZED THEY WERE STILL ON TXWY F. ACR XX WAS THEN CLRED TO TAXI TO RWY 34. TKOF AND FLT WAS MADE WITHOUT FURTHER INCIDENT. BLOWING AND DRIFTING SNOW ALONG WITH DARKNESS CONTRIBUTED TO THE MISTAKE. THERE WAS NEVER ANY ENG RUN-UP, OR BRAKE RELEASE BEFORE MISTAKE WAS DISCOVERED. MISTAKE WAS DISCOVERED BY PLTS EVEN BEFORE REMARKS WERE MADE BY DEN TWR. SUPPLEMENTAL INFO FROM ACN 325690: THIS PROB AROSE MOSTLY BECAUSE OF BLOWING AND DRIFTING SNOW OBSCURING TXWY MARKERS AND LIGHTS.

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.