B757 flight crew reports communications failure on both HF radios and both VHF radios during a fligh...

Narrative:

On several occasions; we were unable to transmit and receive on both captain's and first officer's HF audio panels during the class 2 navigation. It was intermittent during transmission of our position. Once we were within san juan center's airspace; we were unable to communicate on both VHF radios as well. On several occasions we would hear san juan center advising us of a stuck mike. We were unable to transmit on any of the forward radio panels. We tried to troubleshoot by unplugging both headsets and hand held mikes; but were unable to resolve or isolate problem. Several attempts were made on our end to isolate the problem with no success. Since we were unable to communicate with san juan center we elected to squawk 7600. At one point we were totally out of communication with san juan center for a period of 35 to 40 minutes. We had a deadheading first officer that wanted to be in the cockpit for the landing. I asked him to try the mike on the observer's audio panel at which point we were finally successful in communicating with san juan center. At approximately 70 to 80 [NM] north of sxm; my first officer was able to again communicate with ATC using #2 radio only. The landing was uneventful and both audio panels were written up upon landing. A follow up call was made to dispatch and maintenance.

Original NASA ASRS Text

Title: B757 flight crew reports communications failure on both HF radios and both VHF radios during a flight over the western Atlantic to SMX. Communications are reestablished prior to landing using the observer's audio panel. A stuck mic was suggested by ATC.

Narrative: On several occasions; we were unable to transmit and receive on both Captain's and First Officer's HF audio panels during the class 2 navigation. It was intermittent during transmission of our position. Once we were within San Juan Center's airspace; we were unable to communicate on both VHF radios as well. On several occasions we would hear San Juan Center advising us of a stuck mike. We were unable to transmit on any of the forward radio panels. We tried to troubleshoot by unplugging both headsets and hand held mikes; but were unable to resolve or isolate problem. Several attempts were made on our end to isolate the problem with no success. Since we were unable to communicate with San Juan Center we elected to squawk 7600. At one point we were totally out of communication with San Juan Center for a period of 35 to 40 minutes. We had a deadheading First Officer that wanted to be in the cockpit for the landing. I asked him to try the mike on the observer's audio panel at which point we were finally successful in communicating with San Juan Center. At approximately 70 to 80 [NM] north of SXM; my First Officer was able to again communicate with ATC using #2 radio only. The landing was uneventful and both audio panels were written up upon landing. A follow up call was made to Dispatch and Maintenance.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	981651
Time
Date	201111
Local Time Of Day	0601-1200
Place
Locale Reference	ZSU.ARTCC
State Reference	PR
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Air/Ground Communication
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 160 Flight Crew Total 21000 Flight Crew Type 5000
Person 2
Function	Pilot Not Flying First Officer
Experience	Flight Crew Last 90 Days 200 Flight Crew Total 15000 Flight Crew Type 8000
Events
Anomaly	Aircraft Equipment Problem Less Severe

B757 flight crew reports communications failure on both HF radios and both VHF radios during a flight over the western atlantic to smx. Communications are reestablished prior to landing using the observer's audio panel. A stuck mic was suggested by ATC.