Accession Number : AD0826164

Title :   VOR ROTOR MODULATION ANTENNA STUDY.

Descriptive Note : Final rept. no. 1, 16 Sep-30 Nov 67,

Corporate Author : COLLINS RADIO CO DALLAS TX

Personal Author(s) : Robichaux, W. G. ; Griffee, L. V.

Report Date : JAN 1968

Pagination or Media Count : 120

Abstract : The report presents the results of a study to determine a location on the UH-1B (rotary wing) aircraft for a VOR antenna where the effect of the blade rotation on the radiation pattern would be minimized. The patterns were recorded using a one-fourth scale model of the UH-1B aircraft with the main rotor driven or rotated during pattern measurements in order that the magnitude of the rotor modulation could be recorded on the radiation patterns. The VOR antenna was scaled to the same scale as the aircraft model. An analysis of the patterns indicates that minimum modulation was obtained through the use of two identical VOR antennas stacked vertically and fed in phase. (Author)

Descriptors :   *RANGE FINDING), (*AIRCRAFT ANTENNAS, (*HELICOPTERS, OMNIDIRECTIONAL ANTENNAS), MODEL TESTS, LOOP ANTENNAS, DIPOLE ANTENNAS, MODULATION, ANTENNA RADIATION PATTERNS, PERFORMANCE(ENGINEERING), VERY HIGH FREQUENCY, RADIO EQUIPMENT, SITE SELECTION, HELICOPTER ROTORS, ROTARY WINGS, CAPTIVE TESTS.

Subject Categories : Helicopters
      Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE