USE OF UHF RADIOS IN USAF C-141C ACFT IN THE AREA OF PARIS CTL HAS RESULTED IN COMMUNICATION PROBS AS RPTED BY SEVERAL FLT CREWS.
Synopsis
USE OF UHF RADIOS IN USAF C-141C ACFT IN THE AREA OF PARIS CTL HAS RESULTED IN COMMUNICATION PROBS AS RPTED BY SEVERAL FLT CREWS.
Narrative
THERE IS A RECURRING PROB WITH COMS WITH PARIS CTL. THE C-141C IS NOT EQUIPPED WITH 833 VHF RADIOS. SO WE FREQ HAVE TO RELY OUR 2 UHF RADIOS. ON THIS DATE; WHILE FLYING N BOUND ON AIRWAY UN854 BTWN LOGNI AND DJL; WE LOST RADIO CONTACT WITH PARIS CTL (292.7) WE COULD HEAR THE CTLR; BUT THEY COULD NOT HEAR US. WE DO NOT BELIEVE THE PROB WAS WITH EITHER OF OUR RADIOS. (WE HAD NO DIFFICULTY TALKING TO THE SWISS CTLR ON 358.8; OR MARSEILLES CTL ON 249.4. WE DID HAVE TROUBLE TALKING TO PARIS ON 315.5. WE MADE ATTEMPTS ON BOTH RADIOS ON EACH WE COULD HEAR PARIS; BUT THEY COULD NOT HEAR US; SO WE RETURNED TO THE MARSEILLES FREQUENCY 249.4. THE MARSEILLES CTLR ASKED US TO AGAIN TRY 315.5; WHICH WE DID; BUT TO NO ARAIL; AGAIN; WE COULD HEAR PARIS; BUT THEY COULDN'T HEAR US. WE RETURNED TO MARSEILLES ON 249.4 AFTER MULTIPLE ATTEMPTS ON BOTH UHF RADIOS. MARSEILLES ASKED US TO TRY PARIS ON A NEW FREQ 292.7; AND THIS TIME WHEN WE CHKED IN RADIO CONTACT WAS ESTABLISHED.) THE PARIS CTLR ASKED US TO TURN R 30 DEG AND DSND AND MAINTAIN FL 300. I READ BACK THE INSTRUCTION; AND INITIATED THE TURN AND DSCNT. THE CTLR THEN READ THE INSTRUCTION AGAIN. I READ THE INSTRUCTION BACK. THE CTLR DIDN'T RESPOND; SO I BELIEVED WE ONLY HAD ONE-WAY COM (I COULD HEAR HIM; HE COULDN'T HEAR ME.) I SWITCHED TO THE SEC UHF RADIO; TRYING TO RE-ESTABLISH TWO-WAY COM. THE CTLR WAS STILL CALLING US; AND WE WERE STILL RESPONDING- HE COULD NOT HEAR US. THE CTLR ASKED US TO IDENT IF WE COULD HEAR HIM; AND WE DID. WE LEVELED AT FL300; AND CONTINUED ON OUR NEW HEADING WHEN WE ACHIEVED CONTACT WITH PARIS AGAIN WITH CONTACT RE-ESTABLISHED; THE CTLR ASKED US WHY WE 'WE FAILED TO RESPOND AND READ BACK?' HE SAID; 'THIS IS NOT YOUR AIRSPACE AND YOU CAN'T DO AS YOU LIKE.' I TOLD HIM WE RESPONDED WHEN GIVEN INSTRUCTIONS BY READING THEM BACK AND THEN EXECUTING THE DSCNT AND TURN. I TOLD HIM WE TRIED REPEATEDLY ON BOTH RADIOS TO MAKE CONTACT WITH HIM. I TOLD HIM WE IDENTED WHEN I TOLD TO IDENT. WE COMPLIED FULLY WITH HIS INSTRUCTIONS; AND WERE IN CONTINUOUS EFFORT TO RE-ESTABLISH 2-WAY RADIO CONTACT. APPARENTLY HE DIDN'T BELIEVE ME; AND SAID; 'OUR RADIOS ARE TURNED UP. YOU JUST DIDN'T READ BACK.' HE THEN ADDED; 'THIS WILL BE INVESTIGATED.' I CERTAINLY HOPE SO. THIS HAS BEEN AN ON GOING PROB WITH PARIS CTL. I HAVE HEARD FROM NUMEROUS OTHER MIL CREWS WHO'VE HAD UHF PROBS WITH PARIS. I HAD A SIMILAR PROB LAST MONTH; EVENTUALLY RE-ESTABLISHING CONTACT ON VHF GUARD (121.5). I BELIEVE PARIS MUST BE ENCOURAGED TO UPGRADE AND MONITOR THEIR UHF NETWORK; OR MIL NEEDS TO EQUIP OUR ACFT WITH VHF 833 RADIOS. THE AIRSPACE IS TOO CONGESTED IN THIS PART OF EUROPE FOR THIS TO CONTINUE. THE FREQUENT UHF COM PROBLEM IN PARIS AIRSPACE IS A MAJOR HAZARD THAT MUST BE ADDRESSED. I HAVE FILED MIL REPORTS IN THE HOPE THAT THIS ISSUE WILL BE DEALT WITH. UPON REFLECTION OF MY ACTIONS AND THOSE OF MY CREW. I BELIEVE WE DID EVERYTHING WE SHOULD OR COULD HAVE DONE TO MAINTAIN COM AND OPERATE SAFELY; UNFORTUNATELY; IN PARIS' TIGHTLY PACKED AIRSPACE; THIS MAY NOT BE ENOUGH. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE C-141C IS AN AGING ACFT SO THERE IS LITTLE LIKELIHOOD THAT IMPROVED RADIOS WILL BE INSTALLED BEFORE ITS UPCOMING RETIREMENT AND REPLACEMENT WITH A NEW TYPE ACFT. THERE HAS BEEN NO FEEDBACK FROM THE NUMEROUS RPTS THAT HAVE BEEN FILED. ON SUBSEQUENT FLTS INTO THE AREA AND BASED ON INFO FROM OTHER FLT CREWS IT APPEARS THAT PARIS CTL IS AWARE OF THE PROB AS THEY ARE NOW KEEPING THESE ACFT BELOW FL280 WHICH ALLOWS THE USE OF VHF FREQUENCIES FOR SUCCESSFUL COMMUNICATION AND KEEPS THE ACFT BELOW THE RVSM ALTITUDES.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.