History
In geometry, dihedral angle is the angle between two planes. Aviation usage differs slightly from usage in geometry. In aviation, the usage "dihedral" evolved to mean the positive, up angle between the left and right wings. While usage with the prefix "an-" (as in "anhedral") evolved to mean the negative, down angle between the wings.
The aerodynamic stabilizing qualities of dihedral angle were first described by Sir George Cayley in 1808–1809.
Read more about this topic: Dihedral (aircraft)
Famous quotes containing the word history:
“All objects, all phases of culture are alive. They have voices. They speak of their history and interrelatedness. And they are all talking at once!”
—Camille Paglia (b. 1947)
“A poet’s object is not to tell what actually happened but what could or would happen either probably or inevitably.... For this reason poetry is something more scientific and serious than history, because poetry tends to give general truths while history gives particular facts.”
—Aristotle (384–323 B.C.)
“America is, therefore the land of the future, where, in the ages that lie before us, the burden of the World’s history shall reveal itself. It is a land of desire for all those who are weary of the historical lumber-room of Old Europe.”
—Georg Wilhelm Friedrich Hegel (1770–1831)