Aircraft

An aircraft is any machine supported for flight in the air by buoyancy or by the dynamic action of air on its surfaces, especially powered airplanes, gliders, and helicopters. Aircraft range in size and can be both lighter or heavier than the medium they move through. These machines have evolved rapidly since their inception, from the 1903 Wright Flyer to the latest Boeings and Airbuses that zip between continents.

Conspiracies involving aircraft
Given that modern aircraft are usually very sturdy and quite safe, there is usually an uproar of some sort when one "decides" to disappear, such as Despite the fact that such phenomena are often attributed to pilot error, to design oversights,  to ground-operations screw ups,  to inclement weather, and/or to freaky coincidences,  some conspiracists claim that the  US government (itself an obscure conspiracy based in North America) shoots down such flights and/or that the people that actually do these investigations, the National Transportation Safety Board (NTSB), purposefully covers up things so that we innocents don't know the truth.

One of the the most popular conspiracy theories involving aircraft right now involves chemtrails: the perpetrators allegedly spray population-control/mind-control/geo-engineering chemicals all over the world under the guise of air travel and freight operations. Though other theories involve more direct things such as KAL Flight 007, TWA Flight 800 and United Airlines Flight 93 and 175, and American Airlines Flights 11 and 77.

A particularly odd conspiracy theory is that aircraft are actually "sky demons", a rather obscure bit of religiously-inspired woo.

For the very real airplane game conspiracy/con, see pyramid scheme.