A military DC9 practicing instrument approachs to act reports the failure of their ADF receiver.

Attributes
ACN	484531
Time
Date	200009
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : act.airport
State Reference	TX
Altitude	msl single value : 2300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : cos.tower
Operator	other
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Navigation In Use	other ndb
Flight Phase	descent : approach
Route In Use	approach : instrument non precision
Flight Plan	IFR
Person 1
Affiliation	government : military
Function	flight crew : first officer instruction : trainee
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 122 flight time total : 1770 flight time type : 350
ASRS Report	484531
Person 2
Affiliation	government : military
Function	instruction : instructor oversight : pic
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Events
Anomaly	aircraft equipment problem : less severe non adherence : clearance other spatial deviation
Independent Detector	other controllera other flight crewa other flight crewb
Resolutory Action	controller : provided flight assist flight crew : became reoriented flight crew : overcame equipment problem none taken : detected after the fact
Consequence	other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Aircraft

Narrative:

On trainer conducting practice approachs at waco regional, ADF failed causing course deviation. After doing 2 ILS/localizer approachs to runway 17L, we requested the NDB approach to runway 17L. We were cleared direct to leroi to commence the approach. Leroi had been previously tuned and idented (and utilized) on ILS/localizer approachs to runway 17L, and appeared to still be working. As we neared leroi, needle became a little erratic, which looked very much like the 'cone of confusion,' consistent with being in the close proximity of the NAVAID. Noting the deviation, approach inquired about our intentions and then cleared us for a second approach as requested. On the second approach, needle again pointed left which was not consistent with leroi's actual location and approach again inquired about our deviation. At this point, it was obvious that our ADF had failed and we reported it as such. We later tried to tune and identify other NDB's and this confirmed the failure of our ADF.

Original NASA ASRS Text

Title: A MIL DC9 PRACTICING INST APCHS TO ACT RPTS THE FAILURE OF THEIR ADF RECEIVER.

Narrative: ON TRAINER CONDUCTING PRACTICE APCHS AT WACO REGIONAL, ADF FAILED CAUSING COURSE DEV. AFTER DOING 2 ILS/LOC APCHS TO RWY 17L, WE REQUESTED THE NDB APCH TO RWY 17L. WE WERE CLRED DIRECT TO LEROI TO COMMENCE THE APCH. LEROI HAD BEEN PREVIOUSLY TUNED AND IDENTED (AND UTILIZED) ON ILS/LOC APCHS TO RWY 17L, AND APPEARED TO STILL BE WORKING. AS WE NEARED LEROI, NEEDLE BECAME A LITTLE ERRATIC, WHICH LOOKED VERY MUCH LIKE THE 'CONE OF CONFUSION,' CONSISTENT WITH BEING IN THE CLOSE PROX OF THE NAVAID. NOTING THE DEV, APCH INQUIRED ABOUT OUR INTENTIONS AND THEN CLRED US FOR A SECOND APCH AS REQUESTED. ON THE SECOND APCH, NEEDLE AGAIN POINTED L WHICH WAS NOT CONSISTENT WITH LEROI'S ACTUAL LOCATION AND APCH AGAIN INQUIRED ABOUT OUR DEV. AT THIS POINT, IT WAS OBVIOUS THAT OUR ADF HAD FAILED AND WE RPTED IT AS SUCH. WE LATER TRIED TO TUNE AND IDENT OTHER NDB'S AND THIS CONFIRMED THE FAILURE OF OUR ADF.

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.