An airbus 320 on approach at 9 miles between 8000 ft to 6000 ft localizer signal oscillated from sto...

Attributes
ACN	559608
Time
Date	200209
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : san.airport
State Reference	CA
Altitude	msl bound lower : 6000 msl bound upper : 8000
Environment
Light	Night
Aircraft 1
Controlling Facilities	tracon : sct.tracon tower : ewr.tower
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 27 other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	559608
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : #1 and #2 localizer instruments other flight crewa other flight crewb
Resolutory Action	flight crew : overcame equipment problem
Consequence	other other
Supplementary
Problem Areas	Environmental Factor Passenger Human Performance Company
Primary Problem	Passenger Human Performance
Situations
Publication	FAA ADVISORY CIRCULAR 91-21-1A

Narrative:

During approach to san localizer oscillated excessively at about 8000-6000 ft. After landing, it was determined that a passenger had turned on a pda in defiance of our flight attendant request to stow the same. This passenger also said that he did not have to turn it off and presented an article from a paper dated august 2002 stating you can use pda on jets. This was his reason and he had several copies of this article and was waiting for the flight attendant to tell him to turn it off. The passenger sat in xo and is a frequent flyer. I was unable to talk to him as he left prior to my leaving the cockpit. I am absolutely positive that the localizer oscillations were a result of the pda being on and stopped when the unit was turned off. Callback conversation with reporter revealed the following information: the reporter stated that being in a sterile cockpit in front of a locked door and having no contact with the cabin attendant crew the flight crew can be unaware of events happening in the cabin attendant. The reporter said the first hint of trouble was on approach at 9 miles 8000 to 6000 ft when the autoplt on localizer capture began taking 20 degree 'hacks' right and left of the localizer center. The reporter stated the autoplt was following the oscillating localizer needle which was moving from stop to stop. The reporter said the autoplt was disconnected and the airplane was manually flown to an uneventful landing. The reporter stated that on taxi to the gate the tower was advised of the localizer performance and the tower responded that no alarm was received and localizer operation was normal. The reporter said on leaving the cockpit a cabin attendant reported a passenger who refused to turn off a personal digital assistant when ordered to do so by the cabin attendant. The reporter stated the passenger justified his actions by displaying an article in USA today dated august 20 2002, titled 'FAA says you can use pda on jet'. The reporter said he is absolutely certain the pda caused the localizer oscillations. The reporter stated localizer systems were checked by maintenance and no fault found.

Original NASA ASRS Text

Title: AN AIRBUS 320 ON APCH AT 9 MILES BTWN 8000 FT TO 6000 FT LOCALIZER SIGNAL OSCILLATED FROM STOP TO STOP WITH AUTOPLT MAKING 20 DEG DEVIATIONS. CAUSED BY PAX ELECTRONIC DEVICE.

Narrative: DURING APCH TO SAN LOC OSCILLATED EXCESSIVELY AT ABOUT 8000-6000 FT. AFTER LNDG, IT WAS DETERMINED THAT A PAX HAD TURNED ON A PDA IN DEFIANCE OF OUR FA REQUEST TO STOW THE SAME. THIS PAX ALSO SAID THAT HE DID NOT HAVE TO TURN IT OFF AND PRESENTED AN ARTICLE FROM A PAPER DATED AUGUST 2002 STATING YOU CAN USE PDA ON JETS. THIS WAS HIS REASON AND HE HAD SEVERAL COPIES OF THIS ARTICLE AND WAS WAITING FOR THE FA TO TELL HIM TO TURN IT OFF. THE PAX SAT IN XO AND IS A FREQUENT FLYER. I WAS UNABLE TO TALK TO HIM AS HE LEFT PRIOR TO MY LEAVING THE COCKPIT. I AM ABSOLUTELY POSITIVE THAT THE LOC OSCILLATIONS WERE A RESULT OF THE PDA BEING ON AND STOPPED WHEN THE UNIT WAS TURNED OFF. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT BEING IN A STERILE COCKPIT IN FRONT OF A LOCKED DOOR AND HAVING NO CONTACT WITH THE CAB CREW THE FLT CREW CAN BE UNAWARE OF EVENTS HAPPENING IN THE CAB. THE RPTR SAID THE FIRST HINT OF TROUBLE WAS ON APCH AT 9 MILES 8000 TO 6000 FT WHEN THE AUTOPLT ON LOCALIZER CAPTURE BEGAN TAKING 20 DEG 'HACKS' R AND L OF THE LOCALIZER CENTER. THE RPTR STATED THE AUTOPLT WAS FOLLOWING THE OSCILLATING LOCALIZER NEEDLE WHICH WAS MOVING FROM STOP TO STOP. THE RPTR SAID THE AUTOPLT WAS DISCONNECTED AND THE AIRPLANE WAS MANUALLY FLOWN TO AN UNEVENTFUL LNDG. THE RPTR STATED THAT ON TAXI TO THE GATE THE TWR WAS ADVISED OF THE LOCALIZER PERFORMANCE AND THE TWR RESPONDED THAT NO ALARM WAS RECEIVED AND LOCALIZER OP WAS NORMAL. THE RPTR SAID ON LEAVING THE COCKPIT A CAB RPTED A PAX WHO REFUSED TO TURN OFF A PERSONAL DIGITAL ASSISTANT WHEN ORDERED TO DO SO BY THE CAB. THE RPTR STATED THE PAX JUSTIFIED HIS ACTIONS BY DISPLAYING AN ARTICLE IN USA TODAY DATED AUGUST 20 2002, TITLED 'FAA SAYS YOU CAN USE PDA ON JET'. THE RPTR SAID HE IS ABSOLUTELY CERTAIN THE PDA CAUSED THE LOCALIZER OSCILLATIONS. THE RPTR STATED LOCALIZER SYSTEMS WERE CHECKED BY MAINT AND NO FAULT FOUND.

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.

An airbus 320 on approach at 9 miles between 8000 ft to 6000 ft localizer signal oscillated from stop to stop with autoplt making 20 degree deviations. Caused by passenger electronic device.