Charter aircraft has ADF failure.

Attributes
ACN	275940
Time
Date	199407
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sbo
State Reference	GA
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ztl
Operator	other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 135
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : flight engineer pilot : atp pilot : commercial pilot : instrument
Experience	flight time last 90 days : 90 flight time total : 26000 flight time type : 30
ASRS Report	275940
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe conflict : airborne less severe non adherence : clearance non adherence : required legal separation other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	faa : reviewed incident with flight crew Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was given a clearance by ZTL to descend to 4000 ft and proceed direct to the emanuel county ADF radio beacon. I had the beacon tuned in and very faintly idented. I saw the bearing pointer about 60 degrees off the nose to the left so I moved the autoplt heading bug 60 degrees and continued to study the approach chart. After the turn the ADF pointer was about 45 degrees still off to the left so I followed it. I now realized the bearing pointer was not functioning properly so I continued the turn to the left -- almost 360 degrees and the controller called and wanted to know why I made a 360 degree turn. I told him I couldn't get a good 'lock' on the beacon. He said by not going direct to the beacon I came within 4 mi of an airplane climbing through my altitude and this created a 'deviation.' after landing I called my company and reported the ADF as being unreliable. I was assigned an MEL number. I left sbo and proceeded to sav whereas I called the company again. They informed me ZTL had called and reported the deviation. I did not know the ADF would not 'point' as I received an identify signal and there was no history of it being unreliable. By the indications I received I thought I was going direct to the beacon.

Original NASA ASRS Text

Title: CHARTER ACFT HAS ADF FAILURE.

Narrative: I WAS GIVEN A CLRNC BY ZTL TO DSND TO 4000 FT AND PROCEED DIRECT TO THE EMANUEL COUNTY ADF RADIO BEACON. I HAD THE BEACON TUNED IN AND VERY FAINTLY IDENTED. I SAW THE BEARING POINTER ABOUT 60 DEGS OFF THE NOSE TO THE L SO I MOVED THE AUTOPLT HDG BUG 60 DEGS AND CONTINUED TO STUDY THE APCH CHART. AFTER THE TURN THE ADF POINTER WAS ABOUT 45 DEGS STILL OFF TO THE L SO I FOLLOWED IT. I NOW REALIZED THE BEARING POINTER WAS NOT FUNCTIONING PROPERLY SO I CONTINUED THE TURN TO THE L -- ALMOST 360 DEGS AND THE CTLR CALLED AND WANTED TO KNOW WHY I MADE A 360 DEG TURN. I TOLD HIM I COULDN'T GET A GOOD 'LOCK' ON THE BEACON. HE SAID BY NOT GOING DIRECT TO THE BEACON I CAME WITHIN 4 MI OF AN AIRPLANE CLBING THROUGH MY ALT AND THIS CREATED A 'DEV.' AFTER LNDG I CALLED MY COMPANY AND RPTED THE ADF AS BEING UNRELIABLE. I WAS ASSIGNED AN MEL NUMBER. I LEFT SBO AND PROCEEDED TO SAV WHEREAS I CALLED THE COMPANY AGAIN. THEY INFORMED ME ZTL HAD CALLED AND RPTED THE DEV. I DID NOT KNOW THE ADF WOULD NOT 'POINT' AS I RECEIVED AN IDENT SIGNAL AND THERE WAS NO HISTORY OF IT BEING UNRELIABLE. BY THE INDICATIONS I RECEIVED I THOUGHT I WAS GOING DIRECT TO THE BEACON.

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.