Oceanic flight has gross navigation error.

Attributes
ACN	278179
Time
Date	199407
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : vtu
State Reference	CA
Altitude	msl bound lower : 34000 msl bound upper : 34000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : hts
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute : pacific enroute : other oceanic enroute airway : zoa
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 10000 flight time type : 600
ASRS Report	278179
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 21000 flight time type : 210
ASRS Report	277882
Events
Anomaly	non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	Other Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While proceeding eastbound from hnl to lax on echo route, autoplt used to make slight WX deviation using 'heading select' mode. After deviation completed, aircraft failed to recapture 'navigation track' and apparently went into 'heading hold' mode. This failure to capture 'navigation track' went unnoticed by PF. Next chkpoint reached read out as coast point on INS. A call to center was made, center noted approximately 104 mi deviation north of course. At this point, center gave direct vtu VOR. Flight continued without incident.

Original NASA ASRS Text

Title: OCEANIC FLT HAS GROSS NAV ERROR.

Narrative: WHILE PROCEEDING EBOUND FROM HNL TO LAX ON ECHO RTE, AUTOPLT USED TO MAKE SLIGHT WX DEV USING 'HDG SELECT' MODE. AFTER DEV COMPLETED, ACFT FAILED TO RECAPTURE 'NAV TRACK' AND APPARENTLY WENT INTO 'HDG HOLD' MODE. THIS FAILURE TO CAPTURE 'NAV TRACK' WENT UNNOTICED BY PF. NEXT CHKPOINT REACHED READ OUT AS COAST POINT ON INS. A CALL TO CTR WAS MADE, CTR NOTED APPROX 104 MI DEV N OF COURSE. AT THIS POINT, CTR GAVE DIRECT VTU VOR. FLT CONTINUED WITHOUT INCIDENT.

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.