Light aircraft operates into TCA with mode C function of transponder inoperative.

Attributes
ACN	118448
Time
Date	198907
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ont
State Reference	CA
Altitude	msl bound lower : 6500 msl bound upper : 6500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ont tower : stl
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 23 flight time total : 167 flight time type : 80
ASRS Report	118448
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

The VFR flight departed palm springs, california for whiteman airpark, pacoima, california. Aircraft type specified to palm springs departure control was small aircraft /U. While within palm springs departure control airspace, no mention by ATC of an inoperative mode C was made. When I requested VFR radar services from ontario (ont) approach, I again identified aircraft type as small aircraft /U, but ATC said 'report level at 6500'. I began to suspect an inoperative mode C and asked ont approach if they were receiving my mode C readout, they were not. The flight continued through burbank approach control airspace and on to whiteman. Burbank approach control airspace is within the 30 NM radius of the lax TCA, and thus, this portion of the flight must be conducted with an operating mode C transponder, according to far 91.24.

Original NASA ASRS Text

Title: LIGHT ACFT OPERATES INTO TCA WITH MODE C FUNCTION OF TRANSPONDER INOPERATIVE.

Narrative: THE VFR FLT DEPARTED PALM SPRINGS, CALIFORNIA FOR WHITEMAN AIRPARK, PACOIMA, CALIFORNIA. ACFT TYPE SPECIFIED TO PALM SPRINGS DEP CTL WAS SMA /U. WHILE WITHIN PALM SPRINGS DEP CTL AIRSPACE, NO MENTION BY ATC OF AN INOPERATIVE MODE C WAS MADE. WHEN I REQUESTED VFR RADAR SERVICES FROM ONTARIO (ONT) APCH, I AGAIN IDENTIFIED ACFT TYPE AS SMA /U, BUT ATC SAID 'REPORT LEVEL AT 6500'. I BEGAN TO SUSPECT AN INOPERATIVE MODE C AND ASKED ONT APCH IF THEY WERE RECEIVING MY MODE C READOUT, THEY WERE NOT. THE FLT CONTINUED THROUGH BURBANK APCH CTL AIRSPACE AND ON TO WHITEMAN. BURBANK APCH CTL AIRSPACE IS WITHIN THE 30 NM RADIUS OF THE LAX TCA, AND THUS, THIS PORTION OF THE FLT MUST BE CONDUCTED WITH AN OPERATING MODE C TRANSPONDER, ACCORDING TO FAR 91.24.

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.