Editing Flight (section)

=== Buoyant flight ===
{{Main|Aerostat}}
[[File:Goodyear-blimp.jpg|thumb|An airship flies because the upward force, from air displacement, is equal to or greater than the force of gravity]]
Humans have managed to construct lighter-than-air vehicles that raise off the ground and fly, due to their [[buoyancy]] in the air.

An '''aerostat''' is a system that remains aloft primarily through the use of [[buoyancy]] to give an aircraft the same overall density as air. Aerostats include [[balloon (aircraft)|free balloons]], [[airship]]s, and [[moored balloon]]s. An aerostat's main structural component is its [[wikt:envelope|envelope]], a lightweight [[skin]] that encloses a volume of [[lifting gas]]<ref>Walker 2000, p. 541. Quote: the gas-bag of a balloon or airship.</ref><ref>Coulson-Thomas 1976, p. 281. Quote: fabric enclosing gas-bags of airship.</ref> to provide [[buoyancy]], to which other components are attached.

Aerostats are so named because they use "aerostatic" lift, a [[buoyant]] force that does not require lateral movement through the surrounding air mass to effect a lifting force. By contrast, [[Aircraft#Heavier-than-air – aerodynes|aerodynes]] primarily use [[aerodynamic]] [[lift (force)|lift]], which requires the lateral movement of at least some part of the [[aircraft]] through the surrounding air mass.