Heading deviation off airway and heading altitude deviation on final approach course.

Attributes
ACN	113775
Time
Date	198906
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : sna
State Reference	CA
Altitude	msl bound lower : 500 msl bound upper : 24000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla tracon : sna
Operator	general aviation : corporate
Make Model Name	Small Aircraft
Flight Phase	cruise other descent : approach descent other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 50 flight time total : 3000 flight time type : 50
ASRS Report	113775
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot non adherence : published procedure other spatial deviation other spatial deviation
Independent Detector	other controllera
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:

During a 2 hour, 20 min flight from tucson int'l airport to santa ana (orange county/john wayne), I strayed approximately 7 NM +/- south of the airway just north of palm springs while operating on autoplt. During an ILS approach to runway 19R at santa ana, again using the approach mode of the autoplt, the aircraft strayed substantially south off course and low on the glide slope. Glide slope and localizer needles were centered during the entire approach. Tower finally called me to turn 40 degree right at which time I gained a visual sighting of the field. I was approximately 3 NM from touchdown at that time. When I landed, I got an avionics shop manager to check out my VOR with his test equipment and he could not duplicate my problem. He thought the intermittent nature might have been due to a loose wire. I had no difficulties on my return flight the next day.

Original NASA ASRS Text

Title: HEADING DEVIATION OFF AIRWAY AND HEADING ALT DEVIATION ON FINAL APCH COURSE.

Narrative: DURING A 2 HR, 20 MIN FLT FROM TUCSON INT'L ARPT TO SANTA ANA (ORANGE COUNTY/JOHN WAYNE), I STRAYED APPROX 7 NM +/- S OF THE AIRWAY JUST N OF PALM SPRINGS WHILE OPERATING ON AUTOPLT. DURING AN ILS APCH TO RWY 19R AT SANTA ANA, AGAIN USING THE APCH MODE OF THE AUTOPLT, THE ACFT STRAYED SUBSTANTIALLY S OFF COURSE AND LOW ON THE GLIDE SLOPE. GLIDE SLOPE AND LOC NEEDLES WERE CENTERED DURING THE ENTIRE APCH. TWR FINALLY CALLED ME TO TURN 40 DEG RIGHT AT WHICH TIME I GAINED A VISUAL SIGHTING OF THE FIELD. I WAS APPROX 3 NM FROM TOUCHDOWN AT THAT TIME. WHEN I LANDED, I GOT AN AVIONICS SHOP MGR TO CHECK OUT MY VOR WITH HIS TEST EQUIPMENT AND HE COULD NOT DUPLICATE MY PROBLEM. HE THOUGHT THE INTERMITTENT NATURE MIGHT HAVE BEEN DUE TO A LOOSE WIRE. I HAD NO DIFFICULTIES ON MY RETURN FLT THE NEXT DAY.

Data retrieved from NASA's ASRS site as of August 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.