Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification
Aircraft
While cruising at FL370 in foreign airspace my Communications Control Panel (CCP) showed 'panel fail' on the frequency screens. The VHF Number 2 still worked; but the First Officer's CCP would not tune any radios. About 5 minutes later when given a frequency change the Captain's CCP would not tune VHF Number 1 radio as when we tried to change the frequencies it would just go back to the previous frequency. We then started using the Number 2 VHF; tuning it with the Number 3 CCP. The Captain then called Maintenance Control via the Sat phone and attempted to reset the VHF Number 2 radio with no success. We told ATC that we could not change frequencies and he said to stay on the current frequency and we thus used Number 1 VHF. We attempted to use Number 3 VHF as well; but it kept going back into DATA mode for the ACARS. Maintenance researched we could utilize VHF Number 3; i.e. disconnect it from ACARS. They sent us the circuit breakers to pull and sent it to us via ACARS a few minutes later. By this time the Number 2 VHF was the same as Number 1 VHF in that it would not change frequencies; although it transmitted and received. The attempt to disconnect the ACARS from Number 3 VHF was unsuccessful; so the Captain called Maintenance back. We were now around 10 minutes from [the next FIR] so we asked ATC to please call the next FIR for us and notify them that we could only broadcast on our current frequency but were working on the problem. We also advised that we were going to try and reset the radios entirely and might go NORDO. They told us that if we could no longer communicate to squawk 7600 and they would so inform downrange FIRs. Maintenance advised that the reset of all the VHF radios was the only option left and; as we could not change frequencies on any radio; we felt that this was the only option. Maintenance said they had never done an airborne reset as it was usually only done on the ground. But in effect we were NORDO in a few minutes anyway; so we concurred that we should try it. The Captain then pulled all VHF radio circuit breakers and waited one minute. When he pushed them back in all the radios reset and returned to normal function for the rest of the flight. We regained radio communication right around the FIR and continued on as normal to our destination.
An MD-11 on an overland international flight suffered the inability to change VHF comm. frequencies on any of their three comm. radios and was on the verge of going NORDO when they left their current FIR. A fingers crossed full VHF power reset was determined to be the only; albeit untested inflight; possible cure for the problem. As they approached the FIR the reset was initiated and proved successful. The flight continued to destination.