Flush runway inset top assembly for airport guidance light apparatus and guidance light apparatus comprising a top assembly of this type

A flush runway guidance light apparatus comprising:

• a cylindrical steel base embedded in the runway, said base having a flange ring for supporting a top cover flush with the pavement, and a runway inset top assembly comprising
• a cover assembly having a circular shape with a flat top surface and being secured on said flange ring of the base, said cover assembly having an optical system suspended to the underside of it with cover inner means secured to the underside of the cover assembly to form a water-tight enclosure for said optical system,
• said cover assembly having at least one window with optical prism or lens means sealed therein for the passage of each output light beam from the optical system,
• said cover assembly further having a draining aperture in front of each said window;
• and
• at least one channel plate mounted coaxial with the optical axis adjacent the cover assembly,
• said channel plate having an elongated shape with circular arcuate end sides, the curvature of a first of said end sides mating with the curvature of the peripheral edge of the cover assembly so as to be adjacent thereto,
• said channel plate being formed with a longitudinal channel in alignment with said at least one window in the cover assembly for guiding the output light beam passing through said window, with the longitudinal edges and the outer end side of said plate being flush with the flat top surface of the cover assembly and the runway pavement,
• said channel plate being secured in the runway.