when he resumed flying activity in the fall of 1914, dargue began testing a small radio transmitter-receiver built by a local unit, and was damaged again in october experimenting with antenna location. ultimately a wire antenna was paid out behind the aircraft in flight from a reel. further problems of engine noise, ignition interference, burnout of the signal detector by proximity of the transmitter, and loss of calibration from engine vibration were all overcome. on december 1, 1914, dargue and 1st lt. joseph o. mauborgne, the signal corps officer in charge of the fort mills radio station, began a series seven test flights of the radio. during the third, on december 11, the first two-way telegraphy communication with the ground was performed, at a range of for communication with the ground and for the return signal to the airplane, flying at an altitude of , the first radio signal received by an airplane. on the last flight, december 16, using a switch designed to alternate between receiving and transmitting modes, mauborgne conducted the first airborne "conversation" with the ground.