Heading deviation improper FMGC programming.

Attributes
ACN	315779
Time
Date	199509
Day	Tue
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : yul
State Reference	PQ
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : yul
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 8000 flight time type : 250
ASRS Report	315779
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On departure, received clearance to proceed direct to alb, flight planed route. FMGC had unknown position discrepancy, and prompted a turn approximately 90 degrees past the correct heading to proceed directly to alb. Montreal departure informed us that the heading we were turning to would not take us to alb and gave us a turn to the correct heading. At that time, we noted the position error in the FMGC, and completed the remainder of the flight using manual NAVAID tuning and charted courses. There were no other aircraft in the vicinity when the discrepancy occurred, and no aircraft safety was compromised. These events were proceeded by an unfamiliarity with the FMGC requirements that it have entered into it a departure and destination runway. I have only been checked out in the A320 for 3 months, and until this flight, all my flying has been within the united states. The database for the FMGC did not include the montreal dorvil airport, and it was necessary to manually program in a waypoint for the airport. We did that successfully, and was able to complete the inbound flight uneventfully. For the leg outbound, the aircraft position was manually entered, via the latitude/longitude method, and the position was accepted. This FMGC has a peculiarity in that when the thrust levers are advanced for takeoff, it will compute a position update to the end of the specified runway, and begin its further computations from there. What I (we) did not know is that if no runway has been entered (even a pseudo runway), at thrust application, it will search its database, and select the closest runway available. In our case, it apparently chose chicago midway, runway 13C as our departure runway, and built in its bias from that point. From where the FMGC believed it was, alb was located on an approximately course of 090 degrees, rather than the approximately course of 200 degrees from montreal. I have already discussed this situation with our fleet manager, and the head of our training department. Placing additional emphasis on this FMGC's peculiarity, and its requirement to have a runway entered would have definitely prevented this occurrence. Also, had either my first officer or myself had more experience in this particular aircraft, we might have avoided the situation.

Original NASA ASRS Text

Title: HDG DEV IMPROPER FMGC PROGRAMMING.

Narrative: ON DEP, RECEIVED CLRNC TO PROCEED DIRECT TO ALB, FLT PLANED RTE. FMGC HAD UNKNOWN POS DISCREPANCY, AND PROMPTED A TURN APPROX 90 DEGS PAST THE CORRECT HDG TO PROCEED DIRECTLY TO ALB. MONTREAL DEP INFORMED US THAT THE HDG WE WERE TURNING TO WOULD NOT TAKE US TO ALB AND GAVE US A TURN TO THE CORRECT HDG. AT THAT TIME, WE NOTED THE POS ERROR IN THE FMGC, AND COMPLETED THE REMAINDER OF THE FLT USING MANUAL NAVAID TUNING AND CHARTED COURSES. THERE WERE NO OTHER ACFT IN THE VICINITY WHEN THE DISCREPANCY OCCURRED, AND NO ACFT SAFETY WAS COMPROMISED. THESE EVENTS WERE PROCEEDED BY AN UNFAMILIARITY WITH THE FMGC REQUIREMENTS THAT IT HAVE ENTERED INTO IT A DEP AND DEST RWY. I HAVE ONLY BEEN CHKED OUT IN THE A320 FOR 3 MONTHS, AND UNTIL THIS FLT, ALL MY FLYING HAS BEEN WITHIN THE UNITED STATES. THE DATABASE FOR THE FMGC DID NOT INCLUDE THE MONTREAL DORVIL ARPT, AND IT WAS NECESSARY TO MANUALLY PROGRAM IN A WAYPOINT FOR THE ARPT. WE DID THAT SUCCESSFULLY, AND WAS ABLE TO COMPLETE THE INBOUND FLT UNEVENTFULLY. FOR THE LEG OUTBOUND, THE ACFT POS WAS MANUALLY ENTERED, VIA THE LATITUDE/LONGITUDE METHOD, AND THE POS WAS ACCEPTED. THIS FMGC HAS A PECULIARITY IN THAT WHEN THE THRUST LEVERS ARE ADVANCED FOR TKOF, IT WILL COMPUTE A POS UPDATE TO THE END OF THE SPECIFIED RWY, AND BEGIN ITS FURTHER COMPUTATIONS FROM THERE. WHAT I (WE) DID NOT KNOW IS THAT IF NO RWY HAS BEEN ENTERED (EVEN A PSEUDO RWY), AT THRUST APPLICATION, IT WILL SEARCH ITS DATABASE, AND SELECT THE CLOSEST RWY AVAILABLE. IN OUR CASE, IT APPARENTLY CHOSE CHICAGO MIDWAY, RWY 13C AS OUR DEP RWY, AND BUILT IN ITS BIAS FROM THAT POINT. FROM WHERE THE FMGC BELIEVED IT WAS, ALB WAS LOCATED ON AN APPROX COURSE OF 090 DEGS, RATHER THAN THE APPROX COURSE OF 200 DEGS FROM MONTREAL. I HAVE ALREADY DISCUSSED THIS SIT WITH OUR FLEET MGR, AND THE HEAD OF OUR TRAINING DEPT. PLACING ADDITIONAL EMPHASIS ON THIS FMGC'S PECULIARITY, AND ITS REQUIREMENT TO HAVE A RWY ENTERED WOULD HAVE DEFINITELY PREVENTED THIS OCCURRENCE. ALSO, HAD EITHER MY FO OR MYSELF HAD MORE EXPERIENCE IN THIS PARTICULAR ACFT, WE MIGHT HAVE AVOIDED THE SIT.

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.