**Glide angle**

**d equals Distance Flown**

**h equals Change in Height**

**a equals Glide angle**

**depiction of airplane
in angle of descent: two parallel lines, one above and one below the plane with
line tangent to both at left and designated as "h". The line on the
bottom designated as "d" and the two angles created by a line drawn
through the plane connecting both parallel lines, designated as "a".**

**From trigonometry: tan
times (a) equals h over d**