Small aircraft finds 4 degree error on VOR radial. Approach warns close to MOA.

Attributes
ACN	203470
Time
Date	199203
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : tcl
State Reference	AL
Altitude	msl bound lower : 8000 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Route In Use	enroute airway : v18
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 10 flight time total : 1100 flight time type : 1000
ASRS Report	205470
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	other
Situations
Navigational Aid	Unspecified

Narrative:

At approximately 40 NM from tcl, I switched VOR's from tcl to mei. I observed a swing in the VOR needles to the south. Just afterward meridian approach called and said I was near the airway boundary with the meridian MOA. I turned to approximately 200 degree to return to the airway. Navigation by mei VOR. Upon reaching the airway, as indicated by both VOR receivers, I asked meridian approach to verify I was on the airway, and they did. I then rechked my position with respect to the tcl VOR, which indicated I was four degrees south of the airway. Recommended a calibration check of tcl 220 degree radial. In future I will turn one VOR to station above and other behind when approaching a changeover point.

Original NASA ASRS Text

Title: SMA FINDS 4 DEG ERROR ON VOR RADIAL. APCH WARNS CLOSE TO MOA.

Narrative: AT APPROX 40 NM FROM TCL, I SWITCHED VOR'S FROM TCL TO MEI. I OBSERVED A SWING IN THE VOR NEEDLES TO THE S. JUST AFTERWARD MERIDIAN APCH CALLED AND SAID I WAS NEAR THE AIRWAY BOUNDARY WITH THE MERIDIAN MOA. I TURNED TO APPROX 200 DEG TO RETURN TO THE AIRWAY. NAV BY MEI VOR. UPON REACHING THE AIRWAY, AS INDICATED BY BOTH VOR RECEIVERS, I ASKED MERIDIAN APCH TO VERIFY I WAS ON THE AIRWAY, AND THEY DID. I THEN RECHKED MY POS WITH RESPECT TO THE TCL VOR, WHICH INDICATED I WAS FOUR DEGS S OF THE AIRWAY. RECOMMENDED A CALIBRATION CHK OF TCL 220 DEG RADIAL. IN FUTURE I WILL TURN ONE VOR TO STATION ABOVE AND OTHER BEHIND WHEN APCHING A CHANGEOVER POINT.

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.