Aircraft are powered by engines to fly, allowing people and cargo to travel long distances in comfort and safety. The term aircraft is used to describe all types of flying machines, from kites and balloons to fixed wing powered planes like the Boeing 737 and helicopters. The Wright brothers’ first motor-powered airplane, the Eola, flew only 37 meters and stayed in the air for 12 seconds, but it did pave the way for modern commercial flights that travel at over 600 miles per hour with tax-free shopping and onboard entertainment.
When we think of an aircraft, we often picture a jet-powered airplane in the sky, but other categories exist as well. An unpowered glider is a type of aircraft that relies on the downward force of gravity to keep the aircraft in the air, while a parachute-based aircraft, such as the Bell Boeing V-22 Osprey, is an aircraft that depends on engine-driven propellers for lift at low speeds but not at higher ones. There is also a category of aircraft, called rockets, that are not propelled by engine exhaust but rather by self-contained propellants that are ignited and expanded inside the vehicle’s body.
An aircraft can be made out of many materials, but most are built with a specific purpose in mind. For example, a large passenger plane needs to be durable and light, while a military aircraft may need to be strong and fast. Engineers will take all of these factors into consideration when constructing an aircraft, and then choose the materials that will best meet those needs.
The primary component of every aircraft is the fuselage, or body, which contains all of the necessary parts for the flight. The pilots sit in the cockpit, which is located at the front of the fuselage. The passengers and cargo are placed in the back of the fuselage, and the fuel is usually stored in the wings.
Another important factor in the creation of an aircraft is its wing design. The shape of the wing can greatly influence its ability to produce lift and reduce drag, so designers spend a lot of time creating and testing different designs to find one that works best for a given flight. For example, an elliptical wing, such as the Supermarine Spitfire fighter of World War II, is more efficient aerodynamically than a square wing, but it is more likely to stall at a certain angle of attack.
One of the biggest challenges in the field of aviation is understanding how aircraft lift works. Bernoulli’s principle states that air flowing over a curved surface moves faster than the same amount of air in a straight line. This fact has been confirmed by mountains of empirical data from streamlines (lines of smoke particles) in wind-tunnel tests and laboratory experiments using nozzles and Venturi tubes, but Bernoulli’s theorem does not explain why air moves faster across the wing. Specifically, it does not explain why the higher velocity above the wing brings lower pressure with it, rather than high pressure as might be expected.
