C152 pilot has an near midair collision while transiting class C airspace.

Attributes
ACN	728588
Time
Date	200702
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	general aviation : instructional
Make Model Name	Cessna 152
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : zzz.tower
Make Model Name	Small Aircraft Low Wing 2 Eng Retractable Gear
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Flight Plan	VFR
Person 1
Affiliation	other
Function	instruction : trainee
Qualification	pilot : cfi pilot : instrument pilot : commercial pilot : multi engine
Experience	flight time last 90 days : 50 flight time total : 2000 flight time type : 500
ASRS Report	728588
Person 2
Affiliation	other
Function	instruction : instructor
Events
Anomaly	conflict : nmac non adherence : far non adherence : required legal separation
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 0 vertical : 100
Supplementary
Problem Areas	Flight Crew Human Performance Airspace Structure ATC Human Performance
Primary Problem	Ambiguous

Narrative:

We were on our way back from ZZZ1. Right after we passed the golf course a twin engine aircraft came from behind and above us with a distance of no more than 100 ft at a much faster speed. Controller told us that our transponder wasn't on. This wasn't true given that our transponder was set at altitude and the yellow light was constantly blinking. Later the pilot of aircraft communicated to ATC claiming that he saw us and that he was more than 500 ft above us.

Original NASA ASRS Text

Title: C152 PLT HAS AN NMAC WHILE TRANSITING CLASS C AIRSPACE.

Narrative: WE WERE ON OUR WAY BACK FROM ZZZ1. RIGHT AFTER WE PASSED THE GOLF COURSE A TWIN ENG ACFT CAME FROM BEHIND AND ABOVE US WITH A DISTANCE OF NO MORE THAN 100 FT AT A MUCH FASTER SPD. CTLR TOLD US THAT OUR XPONDER WASN'T ON. THIS WASN'T TRUE GIVEN THAT OUR XPONDER WAS SET AT ALT AND THE YELLOW LIGHT WAS CONSTANTLY BLINKING. LATER THE PLT OF ACFT COMMUNICATED TO ATC CLAIMING THAT HE SAW US AND THAT HE WAS MORE THAN 500 FT ABOVE US.

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