Narrative:

En route between atl and ric the radio (ATC) seemed too quiet. We tried a radio check on VHF #1 and got no answer, so tried several frequencys off the lo altitude chart. We thought we had missed the call to go to ZDC from ZTL. We also tried VHF #2. Finally, we got a dc sector on VHF #2 and they answered 'standby.' after about 2 min of absolute silence, I called again. She answered, 'did you get your descent from FL290 to FL270' and she said a different frequency. When I tried to confirm, I could get no answer. The captain stayed at FL290 because he didn't hear the call and I couldn't confirm. We tired the new frequency on both radios and after several tries, heard ATC saying to another aircraft that '(we) had a stuck microphone. I established communication with ZDC on this frequency on VHF #2 and ATC gave us a box pattern descent. We told ATC we thought VHF #1 was bad. Then, on a heading of 090, with richmond airport passing off the left, it was again silent for too long. We could not get the ATC facility on either head of either radio from any position. The so pulled and reset several circuit breakers, we all checked for depressed switches (stuck mikes), etc. We decided we were really lost communication and the captain announced his plan to turn to ric and shoot the published approach. At this time, I made a mistake which caused great consternation on the ground. Intending to set 7600 (the lost communication squawk) in the IFF, I instead set 7500 (hijack). Then, I remembered I should have set 7700 for 1 min prior to lost communication squawk, so I set 7700 then went back to 7500. This really caused consternation on the ground. During this time, we were also trying approach control and ric tower on the radios. Finally, we could hear richmond tower clearing us to land, but they evidently could not hear our responses. Richmond tower then asked us to confirm squawk 7500. At this time, I realized I had set the wrong squawk and switched to 7600. Shortly after, richmond tower started hearing our transmissions, we verbally confirmed the 7500 squawk had been in error, and we were cleared VFR approach. Both heads of both radios checked ok from all position after landing. I met with the person in charge of hijacking response after landing and explained it was my error on the wrong squawk. In thinking this over, we should have been quick to recognize radio failure, and when we started being vectored, should have established further lost communication procedures. I should have been more careful with the IFF setting and, even though we were all quite busy trying radio calls and planning a VFR descent, should have refreshed my memory on the proper squawk with the rest of the crew or the on-board publications. Complete radio failure is relatively uncommon, but one of the things always in the back of my mind from now on will be a plan, just in case.

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Original NASA ASRS Text

Title: FLC OF ACR LGT ACFT LOST COM DURING HIGH ALT CRUISE AND INADVERTENTLY SQUAWKED THE HIJACK CODE ON THE TRANSPONDER INSTEAD OF LOST COM.

Narrative: ENRTE BTWN ATL AND RIC THE RADIO (ATC) SEEMED TOO QUIET. WE TRIED A RADIO CHK ON VHF #1 AND GOT NO ANSWER, SO TRIED SEVERAL FREQS OFF THE LO ALT CHART. WE THOUGHT WE HAD MISSED THE CALL TO GO TO ZDC FROM ZTL. WE ALSO TRIED VHF #2. FINALLY, WE GOT A DC SECTOR ON VHF #2 AND THEY ANSWERED 'STANDBY.' AFTER ABOUT 2 MIN OF ABSOLUTE SILENCE, I CALLED AGAIN. SHE ANSWERED, 'DID YOU GET YOUR DSCNT FROM FL290 TO FL270' AND SHE SAID A DIFFERENT FREQ. WHEN I TRIED TO CONFIRM, I COULD GET NO ANSWER. THE CAPT STAYED AT FL290 BECAUSE HE DIDN'T HEAR THE CALL AND I COULDN'T CONFIRM. WE TIRED THE NEW FREQ ON BOTH RADIOS AND AFTER SEVERAL TRIES, HEARD ATC SAYING TO ANOTHER ACFT THAT '(WE) HAD A STUCK MIKE. I ESTABLISHED COM WITH ZDC ON THIS FREQ ON VHF #2 AND ATC GAVE US A BOX PATTERN DSCNT. WE TOLD ATC WE THOUGHT VHF #1 WAS BAD. THEN, ON A HDG OF 090, WITH RICHMOND ARPT PASSING OFF THE L, IT WAS AGAIN SILENT FOR TOO LONG. WE COULD NOT GET THE ATC FACILITY ON EITHER HEAD OF EITHER RADIO FROM ANY POS. THE SO PULLED AND RESET SEVERAL CIRCUIT BREAKERS, WE ALL CHKED FOR DEPRESSED SWITCHES (STUCK MIKES), ETC. WE DECIDED WE WERE REALLY LOST COM AND THE CAPT ANNOUNCED HIS PLAN TO TURN TO RIC AND SHOOT THE PUBLISHED APCH. AT THIS TIME, I MADE A MISTAKE WHICH CAUSED GREAT CONSTERNATION ON THE GND. INTENDING TO SET 7600 (THE LOST COM SQUAWK) IN THE IFF, I INSTEAD SET 7500 (HIJACK). THEN, I REMEMBERED I SHOULD HAVE SET 7700 FOR 1 MIN PRIOR TO LOST COM SQUAWK, SO I SET 7700 THEN WENT BACK TO 7500. THIS REALLY CAUSED CONSTERNATION ON THE GND. DURING THIS TIME, WE WERE ALSO TRYING APCH CTL AND RIC TWR ON THE RADIOS. FINALLY, WE COULD HEAR RICHMOND TWR CLRING US TO LAND, BUT THEY EVIDENTLY COULD NOT HEAR OUR RESPONSES. RICHMOND TWR THEN ASKED US TO CONFIRM SQUAWK 7500. AT THIS TIME, I REALIZED I HAD SET THE WRONG SQUAWK AND SWITCHED TO 7600. SHORTLY AFTER, RICHMOND TWR STARTED HEARING OUR TRANSMISSIONS, WE VERBALLY CONFIRMED THE 7500 SQUAWK HAD BEEN IN ERROR, AND WE WERE CLRED VFR APCH. BOTH HEADS OF BOTH RADIOS CHKED OK FROM ALL POS AFTER LNDG. I MET WITH THE PERSON IN CHARGE OF HIJACKING RESPONSE AFTER LNDG AND EXPLAINED IT WAS MY ERROR ON THE WRONG SQUAWK. IN THINKING THIS OVER, WE SHOULD HAVE BEEN QUICK TO RECOGNIZE RADIO FAILURE, AND WHEN WE STARTED BEING VECTORED, SHOULD HAVE ESTABLISHED FURTHER LOST COM PROCS. I SHOULD HAVE BEEN MORE CAREFUL WITH THE IFF SETTING AND, EVEN THOUGH WE WERE ALL QUITE BUSY TRYING RADIO CALLS AND PLANNING A VFR DSCNT, SHOULD HAVE REFRESHED MY MEMORY ON THE PROPER SQUAWK WITH THE REST OF THE CREW OR THE ON-BOARD PUBLICATIONS. COMPLETE RADIO FAILURE IS RELATIVELY UNCOMMON, BUT ONE OF THE THINGS ALWAYS IN THE BACK OF MY MIND FROM NOW ON WILL BE A PLAN, JUST IN CASE.

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