A319 autoplt appears unable to compensate for strong crosswinds in holding pattern.

Attributes
ACN	797081
Time
Date	200807
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : etg.vortac
State Reference	PA
Altitude	msl single value : 33000
Aircraft 1
Controlling Facilities	artcc : zob.artcc tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	A319
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 250 flight time total : 7000 flight time type : 1700
ASRS Report	797081
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe non adherence : far other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued advisory flight crew : returned to intended or assigned course
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Environmental Factor Flight Crew Human Performance Aircraft
Primary Problem	Environmental Factor
Air Traffic Incident	Pilot Deviation

Narrative:

We were instructed to hold on the airway as published at miget intersection. It was a direct entry into the hold. The inbound course was 109 degrees. The winds were 206 degrees at 96 KTS. The A319 calculated its holding track and applied the proper wind correction flying outbound. However; the track didn't compensate for the shallow bank turn back inbound to the 109 degree course. The aircraft flew about 3.5 mi north of the airway. The second time around had the same result. Thinking we were still 'within limits' of the airway; we let it proceed. The controller requested we keep the inbound turn closer to the airway. So; the next outbound turn we manually flew in heading mode to fly further south than the A319 predetermined outbound course. Turning inbound resulted in lining up perfectly with the 109 degree course. In strong xwinds; do not trust the autoplt to compensate for the winds. It will crab outbound to maintain its course; but be blown right past the inbound course when turning inbound.

Original NASA ASRS Text

Title: A319 AUTOPLT APPEARS UNABLE TO COMPENSATE FOR STRONG CROSSWINDS IN HOLDING PATTERN.

Narrative: WE WERE INSTRUCTED TO HOLD ON THE AIRWAY AS PUBLISHED AT MIGET INTXN. IT WAS A DIRECT ENTRY INTO THE HOLD. THE INBOUND COURSE WAS 109 DEGS. THE WINDS WERE 206 DEGS AT 96 KTS. THE A319 CALCULATED ITS HOLDING TRACK AND APPLIED THE PROPER WIND CORRECTION FLYING OUTBOUND. HOWEVER; THE TRACK DIDN'T COMPENSATE FOR THE SHALLOW BANK TURN BACK INBOUND TO THE 109 DEG COURSE. THE ACFT FLEW ABOUT 3.5 MI N OF THE AIRWAY. THE SECOND TIME AROUND HAD THE SAME RESULT. THINKING WE WERE STILL 'WITHIN LIMITS' OF THE AIRWAY; WE LET IT PROCEED. THE CTLR REQUESTED WE KEEP THE INBOUND TURN CLOSER TO THE AIRWAY. SO; THE NEXT OUTBOUND TURN WE MANUALLY FLEW IN HDG MODE TO FLY FURTHER S THAN THE A319 PREDETERMINED OUTBOUND COURSE. TURNING INBOUND RESULTED IN LINING UP PERFECTLY WITH THE 109 DEG COURSE. IN STRONG XWINDS; DO NOT TRUST THE AUTOPLT TO COMPENSATE FOR THE WINDS. IT WILL CRAB OUTBOUND TO MAINTAIN ITS COURSE; BUT BE BLOWN RIGHT PAST THE INBOUND COURSE WHEN TURNING INBOUND.

Data retrieved from NASA's ASRS site as of May 2009 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.