On 5 April 2013, a Mitsubishi MU‑2B aircraft, registered N64MD, departed Honiara, Solomon Islands with two pilots on board. The purpose of the flight was to ferry the aircraft from Honiara to Essendon, Victoria, with an intermediate stop at Townsville, Queensland.
Shortly after take-off at Townsville, both pilots received a considerable amount of static in their headsets. Townsville Tower air traffic control (ATC) then instructed the crew to transfer to the Townsville Approach frequency. The pilot in command (PIC) read back the instruction; however, ATC advised that he was transmitting carrier wave only (no voice communications were heard).
About 5 minutes after the aircraft departed, Townsville ATC offered the crew the option of returning to Townsville. The PIC reported that they could hear the transmissions made by Townsville ATC, but were unable to return to as the fuel quantity in each wing tip tank was in excess of the maximum landing limitation and the aircraft was carrying additional fuel in the ferry tank. The PIC was unable to advise Townsville ATC of this as the aircraft’s very high frequency (VHF) radios were now inoperable. Consequently, the PIC elected to continue the flight as per the submitted flight plan.
The PIC attempted to resolve the radio problem, but without success. Townsville ATC, Brisbane Centre ATC and Melbourne Centre ATC also continued attempts to establish communications with the crew.
When about 230 NM north of Essendon, Victoria communications with ATC were re-established. The crew were not in normal communications with ATC for about 3 hours and 35 minutes.
An examination of the radio determined that water leakage from a small access door had corroded two main radio isolator breakers/switches, which subsequently resulted in the radio failure.
It is important that ATC is made aware of any problems as soon as possible. This provides ATC with sufficient time to manage a situation, rather than having to react when an issue has developed into a major problem. In the event of a communications failure, it is important that pilots follow the appropriate procedure, and if communications cannot be re-established, consider utilising alternative methods such as mobile telephones.