Power line communication system on aircraft

A method includes coupling a vehicle to an electrical umbilical comprising a supply end, a plug end and an electrical conductor extending therebetween, said plug end configured to mate with the vehicle such that power is supplied to the vehicle through the electrical conductor from the supply end; the method also uses a first interface device electrically coupled to the supply end and a network access point, the first interface device configured to: transmit and receive data carrier signals though the electrical conductor while power is supplied to the vehicle through the electrical conductor; and convert the data carrier signals from and to a predetermined data format on the network; and a second interface device electrically coupled to the plug end when the umbilical is coupled to the vehicle, said interface device configured to transmit and receive the data carrier signals with the first interface device while power is supplied to the aircraft through the electrical conductor.