Characteristics of Airplane Antennas for Radio Range Beacon Reception

This paper gives the results of an investigation on the characteristics of airplane receiving antennas to determine whether an antenna arrangement could be devised which would have all the desirable electrical properties of the vertical pole antenna and yet be free from the mechanical difficulties encountered in the use of the pole antenna. The antennas studied include the inclined antenna with both forward and backward inclination, the horizontal dipole antenna, the horizontal L antenna, the horizontal V antenna, the inclined V antenna, the symmetrical transverse T antenna, and the symmetrical longitudinal T antenna. A theoretical treatment is given which enables the voltage induced by a radio range beacon transmitting station to be calculated for any receiving antenna in space. This theoretical analysis is used to determine the received voltage, course error, and localizing effect for each of the antenna types studied. An experimental study was also made to check the theoretical analysis. The results obtained by experiment check very well with the theoretical predictions for each type of antenna. The symmetrical transverse T antenna and the symmetrical longitudinal T antenna, with vertical lead-in portions, are both found to fulfill the desired requirements. Neither of these antennas show any course errors, and give the same received voltage as the vertical pole antenna having much greater actual height, thus reducing the mechanical troubles caused by vibration and ice formation.