PA28 PLT CHALLENGES AZO ABOUT A D328 NMAC.

Narrative

WHILE ENRTE ON AN IFR CLRNC FROM ATW VIA MKG-FWA DIRECT I17; IN LEVEL FLT AT 7000 FT MSL; 7 MI W OF AZO; DO328 APCHED FROM THE 10 O'CLOCK POS IN A CLB AND PASSED DIRECTLY OVER US BY 150-200 FT. WE HAD BEEN TALKING TO GRR APCH AND COULD STILL HEAR THEM. WE RECOGNIZED WE WERE ABEAM AZO AND SHOULD HAVE BEEN HANDED OFF TO AZO APCH. THIS WAS WHEN WE SAW THE DO328. WE TRIED TO CONTACT GRR APCH AT LEAST 3 TIMES WITH NO RESPONSE. WE LOOKED UP AZO APCH'S FREQ AND CONTACTED THEM. WE ADVISED AZO OF THE NMAC; OUR APPROX POS AND ASKED IF THEY HAD AN IFR STRIP ON US. AZO ADVISED THAT THEY DID HAVE AN IFR STRIP ON US. SUBSEQUENT CONVERSATION INDICATED THAT GRR APCH HAD NOT HANDED US OFF TO AZO APCH. WE HAD BEEN HAVING PROBS WITH OUR XPONDER. GRB HAD INITIALLY RPTED THE XPONDER INOP. GRB GAVE US A NEW CODE AND ADVISED THAT THE XPONDER WAS WORKING. MKG INITIALLY ADVISED THEY HAD A PROB RECEIVING OUR XPONDER THEN ADVISED THEY HAD US. GRR INITIALLY ADVISED THEY WERE HAVING A PROB RECEIVING OUR XPONDER. I DO NOT RECALL IF GRR EVER DID RECEIVER OUR XPONDER. ALL THROUGH THE FLT; WE WERE GETTING A REPLY LIGHT AND THE IDENT RESPONDED ON THE XPONDER. IT APPEARS THAT THE GRR CTLR LOST TRACK OF A NON XPONDER ACFT AND FAILED TO HAND US OFF TO AZO IN A TIMELY MANNER.