MD80 flight crew receives a TCASII RA while on 6 mi final to mco and executes a climb evasive maneuv...

Attributes
ACN	439232
Time
Date	199906
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : orl.vortac
State Reference	FL
Altitude	msl single value : 3500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mco.tracon
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	439232
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	other anomaly other
Independent Detector	aircraft equipment : tcas
Resolutory Action	controller : issued new clearance flight crew : executed missed approach flight crew : took evasive action
Supplementary
Problem Areas	Company
Primary Problem	Company

Narrative:

While on final to runway 18L at mco and at about 3500 ft MSL over the civil airport 6 NM north of mco while cleared for the visual approach to runway 18L, we received an instantaneous climb RA of about 1800 FPM. We started the climb and informed the tower and the clear of conflict message followed our initiation of a climb almost immediately. We abandoned the approach and with tower clearance circled back for an uneventful landing on runway 18L. We never saw any traffic in our area. On taxi in to the gate, tower informed us that someone had tested a transponder at the airport we overflew and that similar occurrences had been experienced in the past. Hope this will provide a heads up for the future. Callback conversation with mco TRACON specialist revealed the following information: there were known instances of unshielded transponder testing incidents causing false TCASII RA's at an electronic repair facility at orl airport. An mco TRACON representative had called the repair facility questioning maintenance practices. Someone at the electronic repair facility acknowledged that such unshielded incidences could have occurred.

Original NASA ASRS Text

Title: MD80 FLC RECEIVES A TCASII RA WHILE ON 6 MI FINAL TO MCO AND EXECUTES A CLB EVASIVE MANEUVER. NO TFC OBSERVED BY FLC, BUT ADVISED ON GND CTL THAT MAINT XPONDER TESTING WAS BEING CONDUCTED AT SDF ARPT.

Narrative: WHILE ON FINAL TO RWY 18L AT MCO AND AT ABOUT 3500 FT MSL OVER THE CIVIL ARPT 6 NM N OF MCO WHILE CLRED FOR THE VISUAL APCH TO RWY 18L, WE RECEIVED AN INSTANTANEOUS CLB RA OF ABOUT 1800 FPM. WE STARTED THE CLB AND INFORMED THE TWR AND THE CLR OF CONFLICT MESSAGE FOLLOWED OUR INITIATION OF A CLB ALMOST IMMEDIATELY. WE ABANDONED THE APCH AND WITH TWR CLRNC CIRCLED BACK FOR AN UNEVENTFUL LNDG ON RWY 18L. WE NEVER SAW ANY TFC IN OUR AREA. ON TAXI IN TO THE GATE, TWR INFORMED US THAT SOMEONE HAD TESTED A XPONDER AT THE ARPT WE OVERFLEW AND THAT SIMILAR OCCURRENCES HAD BEEN EXPERIENCED IN THE PAST. HOPE THIS WILL PROVIDE A HEADS UP FOR THE FUTURE. CALLBACK CONVERSATION WITH MCO TRACON SPECIALIST REVEALED THE FOLLOWING INFO: THERE WERE KNOWN INSTANCES OF UNSHIELDED XPONDER TESTING INCIDENTS CAUSING FALSE TCASII RA'S AT AN ELECTRONIC REPAIR FACILITY AT ORL ARPT. AN MCO TRACON REPRESENTATIVE HAD CALLED THE REPAIR FACILITY QUESTIONING MAINT PRACTICES. SOMEONE AT THE ELECTRONIC REPAIR FACILITY ACKNOWLEDGED THAT SUCH UNSHIELDED INCIDENCES COULD HAVE OCCURRED.

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.

MD80 flight crew receives a TCASII RA while on 6 mi final to mco and executes a climb evasive maneuver. No traffic observed by flight crew, but advised on ground control that maintenance transponder testing was being conducted at sdf airport.