Crew reports multiple occurrences of bend in the sli VOR 080 degree radial at about 50 mi.

Attributes
ACN	448224
Time
Date	199909
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : sli.vortac
State Reference	CA
Altitude	msl bound lower : 12000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sct.tracon tower : lga.tower
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	climbout : intermediate altitude
Route In Use	departure sid : prd.o5
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : multi engine
ASRS Report	448224
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
ASRS Report	448225
Events
Anomaly	other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Supplementary
Problem Areas	Environmental Factor Aircraft Navigational Facility
Primary Problem	Navigational Facility
Situations
Navigational Aid	SLI.VORTAC

Narrative:

Possible VOR signal/radial problem seal beach VORTAC. Location: approximately sli 080 degree radial, 50 DME. While climbing to 14000 ft on the prado 5 departure we were told by ATC that we were 2 mi north of course. Both our vors were set on the sli 080 degree radial and showed centerline. After a few mins, ATC then turned us right to a heading of 140 degrees. Told ATC we indicated centerline. No loss of separation was mentioned. This same situation has happened at least 2 or 3 times to me in just about the same position. Come to find out the first officer has experienced this also 2 times on the prado 5 out of ont. Perhaps there is an electrical distortion and/or receiver problem in this area. Perhaps it was a cell phone or other electrical device in the cabin. We mentioned this to the flight attendant, however, she recalled nothing unusual. We were not using GPS LNAV at the time.

Original NASA ASRS Text

Title: CREW RPTS MULTIPLE OCCURRENCES OF BEND IN THE SLI VOR 080 DEG RADIAL AT ABOUT 50 MI.

Narrative: POSSIBLE VOR SIGNAL/RADIAL PROB SEAL BEACH VORTAC. LOCATION: APPROX SLI 080 DEG RADIAL, 50 DME. WHILE CLBING TO 14000 FT ON THE PRADO 5 DEP WE WERE TOLD BY ATC THAT WE WERE 2 MI N OF COURSE. BOTH OUR VORS WERE SET ON THE SLI 080 DEG RADIAL AND SHOWED CTRLINE. AFTER A FEW MINS, ATC THEN TURNED US R TO A HDG OF 140 DEGS. TOLD ATC WE INDICATED CTRLINE. NO LOSS OF SEPARATION WAS MENTIONED. THIS SAME SIT HAS HAPPENED AT LEAST 2 OR 3 TIMES TO ME IN JUST ABOUT THE SAME POS. COME TO FIND OUT THE FO HAS EXPERIENCED THIS ALSO 2 TIMES ON THE PRADO 5 OUT OF ONT. PERHAPS THERE IS AN ELECTRICAL DISTORTION AND/OR RECEIVER PROB IN THIS AREA. PERHAPS IT WAS A CELL PHONE OR OTHER ELECTRICAL DEVICE IN THE CABIN. WE MENTIONED THIS TO THE FLT ATTENDANT, HOWEVER, SHE RECALLED NOTHING UNUSUAL. WE WERE NOT USING GPS LNAV AT THE TIME.

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.