Heading track position deviation of atx noted by ATC controller.

Attributes
ACN	279476
Time
Date	199408
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ome
State Reference	AK
Altitude	msl bound lower : 10000 msl bound upper : 10000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tower : jfk
Operator	common carrier : air taxi
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 135
Flight Phase	cruise other
Route In Use	enroute airway : zan
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : atp
Experience	flight time last 90 days : 280 flight time total : 8000 flight time type : 1000
ASRS Report	279476
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe non adherence : clearance non adherence : far other spatial deviation
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

During cruise flight on IFR flight plan, center advised me that I was 10 mi off course. The #1 CDI needle was near center but when I glanced at the #2 CDI it showed off course. Upon return to base I notified the mechanics and they replaced the #1 panel unit (HSI). There was no 'off' flag when the CDI improperly centered. A better instrument scan would have probably helped. The 30-day VOR check was current.

Original NASA ASRS Text

Title: HDG TRACK POS DEV OF ATX NOTED BY ATC CTLR.

Narrative: DURING CRUISE FLT ON IFR FLT PLAN, CTR ADVISED ME THAT I WAS 10 MI OFF COURSE. THE #1 CDI NEEDLE WAS NEAR CTR BUT WHEN I GLANCED AT THE #2 CDI IT SHOWED OFF COURSE. UPON RETURN TO BASE I NOTIFIED THE MECHS AND THEY REPLACED THE #1 PANEL UNIT (HSI). THERE WAS NO 'OFF' FLAG WHEN THE CDI IMPROPERLY CTRED. A BETTER INST SCAN WOULD HAVE PROBABLY HELPED. THE 30-DAY VOR CHK WAS CURRENT.

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.