EQUIPMENT AND METHOD FOR MAKING VISIBLE THE APPROACH AND LANDING PATH OF AIRCRAFT IN LOW VISIBILITY WEATHER

摘要

1455358 Visual signalling for aircraft landing L EIGENMANN 29 March 1974 13972/74 Heading G4F An aircraft landing aid comprises visually recognizable devices at intervals along the glide path. Such devices may be the peaks of jets of water containing matter readily seen in low visibility or the peaks of ballistic trajectories or helium-inflated balloons moored to the ground Arrangements are included for recirculating anything sent up. In the case of jets of liquid, the liquid may be hygroscopic (e.g. glycerol, ethylene glycol, propylene glycol) which absorb the water droplets in fog and low clouds thereby affording a clearer atmosphere over the intervals of the glide path. Ballistic bodies may be fracturable spherical envelopes containing water, the envelopes being of pigment or coated with luminescent or phosphorescent material. A control system for maintaining water jet peaks at the correct heights is outlined. It is preferable that the glide path defined is just below the glide path to be followed.