B757 CREW LANDS AT ZZZZ WITHOUT CLRNC.

Narrative

ON APCH TO ZZZZ AND TOLD WE WERE TO DSND TO 5000 FT TO ZZZZ FOR STRAIGHT IN APCH AND WE WERE #1. THEN HEARD ANOTHER ACR WAS TOLD TO DSND TO 3000 FT AND TOLD STRAIGHT TO ZZZZ FOR STRAIGHT IN APCH AND #1. WE WERE 25 NM FROM ZZZZ AND OTHER ACR 30 NM. CAPT EXPLAINED TO APCH THAT WE WERE BOTH GIVEN SAME CLRNC AND WE WERE CLOSER. WE COULD SEE AIRPLANE ON TCAS AND COLLISION COURSE OBVIOUS TO US. APCH THEN STOPPED OTHER ACR AT 5000 FT AND CLRED US FOR APCH TO LAND #1. THEN WE HAD DIFFICULTY CONTACTING APCH; RADIO WAS SILENT WITH CAPT CALLING. ALSO TRIED ON TWR FREQ AND NO LUCK. AS WE WERE UNSURE OF THE DIRECTION OF OTHER ACR WE CONTINUED APCH AND CAPT USED EMER AUTH TO LAND WITHOUT A CLRNC AS THIS SEEMED THE SAFE COURSE OF ACTION WITH THE OTHER ACR OVERHEAD THE ARPT. CONTACT WAS MADE AT TOUCHDOWN WITH APCH. THEY WERE ONLY FREQ WORKING FOR APCH; TWR AND GND AT THIS TIME. NO MENTION WAS MADE BY APCH OF THE RADIO SILENCE WHEN LNDG CLRNC WAS REPEATEDLY REQUESTED OR THE LNDG WITHOUT A CLRNC. THEY CLRED US TO TAXI TO GATE. SUPPLEMENTAL INFO FROM ACN 708010: GOING AROUND WAS NOT AN OPTION; BECAUSE WE DID NOT KNOW WHERE ACR Y WAS; IN A NON-RADAR ENVIRONMENT; AT 5000 FT AT ZZZZ; WHICH IS AT THE ARPT.