| 摘要 |
<p>A location signalling device comprising a wing balloon for signalling a location. The wing balloon is fixed to a tether line that itself is fixed to the location to be signalled. The wing balloon has an inflatable aerodynamically shaped hollow body to be at least partly be filled with a lighter-than-air gas and having a wing attack surface for air flowing relative to said wing balloon. The floating aloft of said wing balloon is supported by said air flow. When the wing balloon is inflated, a flexible wing portion is passively variable. The stronger the wind, the less attack is given. Thus, the dragging force on the tether line is generally static.</p> |
