A boeing 727 flight crew drifted left of track on descent into iad.

Attributes
ACN	456270
Time
Date	199911
Day	Thu
Local Time Of Day	1801 To 2400
Place
State Reference	VA
Altitude	msl single value : 24000
Environment
Light	Night
Aircraft 1
Controlling Facilities	artcc : zdc.artcc tracon : c90.tracon
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	arrival star : coate 3
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	456270
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
ASRS Report	456269
Events
Anomaly	non adherence : clearance non adherence : published procedure other spatial deviation
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance other
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was PNF while descending on the coate 3 arrival into iad. I took control of the aircraft to check a suspected autoplt problem. Disengaged autoplt and found no problem. Gave aircraft back to copilot and made my arrival PA. When I returned to the radio after PA noticed auxiliary navigation was not engaged and that we had drifted slightly left of the proper radial. Spoke to center and was cleared direct to falko. Rest of flight and CAT ii approach uneventful. Supplemental information from acn 456269: control of aircraft was given to captain to check a trim condition, autoplt was turned off. Upon xfer of control back to me, autoplt was re-engaged but I forgot to re-select auxiliary/navigation.

Original NASA ASRS Text

Title: A BOEING 727 FLC DRIFTED L OF TRACK ON DSCNT INTO IAD.

Narrative: I WAS PNF WHILE DSNDING ON THE COATE 3 ARR INTO IAD. I TOOK CTL OF THE ACFT TO CHK A SUSPECTED AUTOPLT PROB. DISENGAGED AUTOPLT AND FOUND NO PROB. GAVE ACFT BACK TO COPLT AND MADE MY ARR PA. WHEN I RETURNED TO THE RADIO AFTER PA NOTICED AUX NAV WAS NOT ENGAGED AND THAT WE HAD DRIFTED SLIGHTLY L OF THE PROPER RADIAL. SPOKE TO CTR AND WAS CLRED DIRECT TO FALKO. REST OF FLT AND CAT II APCH UNEVENTFUL. SUPPLEMENTAL INFO FROM ACN 456269: CTL OF ACFT WAS GIVEN TO CAPT TO CHK A TRIM CONDITION, AUTOPLT WAS TURNED OFF. UPON XFER OF CTL BACK TO ME, AUTOPLT WAS RE-ENGAGED BUT I FORGOT TO RE-SELECT AUX/NAV.

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.