What is glide slope?

Some articles on glide slope, glide, slope:

Sailplane - Glide Slope Control
... Pilots need some form of control over the glide slope to land the glider ... Glide slope is the distance traveled for each unit of height lost ... In a steady wings-level glide with no wind, glide slope is the same as the lift/drag ratio (L/D) of the glider, called "L-over-D" ...
Visual Approach Slope Indicator - Types - Tri-colored VASI
... VASI is a single light that appears amber above the glide slope, green on the glide slope and red below it ... While on approach, the colour amber (above slope) can be seen at a very thin angle of approach between green (on slope) and red (below slope) due to the mixing of red and green which gives an amber colour ... Pilots not familiar with this may see the amber light and think they are above glide slope and then descend rather than make the proper correction ...
Optical Landing System - Components - Lights
... reference against which he may judge his position relative to the glide slope ... source") — indicates the relative position of the aircraft with reference to glide slope ... The further the aircraft is from the glide slope, the further the ball will be above or below the datum lights ...

Famous quotes containing the word glide:

    Our life is not so much threatened as our perception. Ghostlike we glide through nature, and should not know our place again.
    Ralph Waldo Emerson (1803–1882)