This week the German chancellor's plane (an Airbus A340-300) had to abort the flight due to loss of communications. The newspaper write they only had a satellite phone left1:
Die Kommunikationssysteme waren ausgefallen, sodass kein Kontakt zum Boden möglich war. [Der Pilot] musste deshalb per Satellitentelefon mit dem Flughafen Köln/Bonn die ungeplante Landung vorbereiten.
The communication systems failed, contacting the ground wasn't possible. The satellite phone had to be used to prepare the landing.
Man gehe derzeit von einem Fehler in einer elektronischen Verteilerbox aus, die sowohl die Funkanlage als auch das System zum Ablassen des Kerosins steuere, hieß es von der Luftwaffe.
Currently an error in a distribution box is most likely. The box services the radio as well as the fuel dumping system.
Is the antenna for the satellite uplink an integral part of the air plane? As suggested here for WiFi. I assume satellite phone doesn't work from inside the plane without an external antenna, is this correct?
Maybe this is nitpicking, but when the satellite phone is build into the airplane, with the necessary tracking, why is this not considered part of the communications system?
How come that seemingly crucial yet quite simple two way radio can fail and is not powered by some very basic passive turbine? How much power is approximately required by the radio?