Autopsy of unmanned airship television broadcast

A number of telecommunications experiments were flown on an autonomous, 68 metre non-rigid airship in November 2004 as part of a national R&D project for stratospheric platform systems [1]. Although the digital television broadcast experiment was successful, it was found that the signal was occasionally entirely lost when the airship passed directly over one receiving station. A quarter wavelength monopole on a simple model of the airship gondola was studied using a commercially available MOM software. Conclusions were drawn about the effects of various gondola features upon the radiation pattern of the monopole, and recommendations are made for future gondola design.