Audio Control Panel 1 and Audio Control Panel 2, which both malfunctioned after a pilot spilled his coffee during a flight from Germany to Mexico.
A transatlantic flight was forced to divert to the Republic of Ireland because a pilot spilled a cup of coffee on the aircraft's controls, it has emerged.
The report found the 49-year-old captain had put his coffee cup on a tray table - where objects are "vulnerable to being knocked over" - despite Airbus recommending pilots use the cup holders provided.
The hot liquid damaged an audio control panel, producing an electrical burning smell and smoke, an accident report revealed. The panel on the co-pilot's side began to heat up, and a button started to melt before the panel quit working.
When a small amount of smoke was spotted, the decision was made to divert to Shannon.
The report explains: "The various ACP failures resulted in communication difficulties". The commander was not able to receive or transmit and could only hear transmissions through the co-pilot's speaker.
"During the diversion, the flight crew alternately used supplementary oxygen, with one pilot on oxygen at all times", the bulletin stated.
The Department for Transport report does not say which airline was involved in the incident, but Condor - which is part of British travel company Thomas Cook Group - confirmed that it operated the flight.
A spokesperson for the airline told PEOPLE that the diversion was a "precautionary measure" and that the aircraft was "fully inspected and repaired" in Ireland and then continued its route to Cancun via Manchester.
It was not clear what caused the second panel to fail.
"We have comprehensively investigated this incident and reviewed the procedures of liquids in the cockpit".
They have also provided lids for all coffee cups on board.
The airline responded to the accident by ensuring cup lids are provided on all flights.