DC9 crew tracked wrong radial for filed airway.

Attributes
ACN	431907
Time
Date	199903
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : las.vortac
State Reference	NV
Altitude	msl single value : 33000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zlc.artcc
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : level
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 : 9000 flight time type : 2000
ASRS Report	431907
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : became reoriented
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

When we reached las VOR, we tracked outbound on the wrong radial for the filed airway. We were tracking approximately 20 degrees off course for about 120 NM. ATC advised us, or asked 'where are you going?' we thought that we were on the airway, but when ATC asked us where we were going, we discovered our error and asked for direct slc. Direct slc was assigned.

Original NASA ASRS Text

Title: DC9 CREW TRACKED WRONG RADIAL FOR FILED AIRWAY.

Narrative: WHEN WE REACHED LAS VOR, WE TRACKED OUTBOUND ON THE WRONG RADIAL FOR THE FILED AIRWAY. WE WERE TRACKING APPROX 20 DEGS OFF COURSE FOR ABOUT 120 NM. ATC ADVISED US, OR ASKED 'WHERE ARE YOU GOING?' WE THOUGHT THAT WE WERE ON THE AIRWAY, BUT WHEN ATC ASKED US WHERE WE WERE GOING, WE DISCOVERED OUR ERROR AND ASKED FOR DIRECT SLC. DIRECT SLC WAS ASSIGNED.

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.