Airplanes

What is an airplane? 

An airplane is a vehicle that has wings and one or more engines and is capable of moving through the air. The word aircraft is also commonly used to refer to planes, though it can actually be used for other types of vehicles, such as helicopters. 

What types of planes are there? 

Airplanes can be classified according to their shape, their engine, their weight, etc. Here, we will use a less technical classification, classification according to its use:

• Passenger plane: these are built specifically to transport groups of people; they’re used by airlines for commercial flights, though they can also be private. They are equipped with pressurized cabins and certain features like seats, toilets, screens, and small kitchens.
• Cargo plane: these are used to transport goods and large objects. They don’t have seats or other elements needed to transport people. They usually have a wider fuselage to have more storage space; higher wings so the load is closer to the ground when grounded; more wheels; and higher tails since loading and unloading usually occurs through a back door.
• Military plane: it is used for wartime purposes. While passenger and cargo aircraft can also be military (rather than civilian), this label is for attack or defense aircraft. There are many types of military aircraft, according to their purposes. For instance, they could bombers, capable of transporting and dropping bombs or missiles; or fighter planes designed and equipped to intercept and shoot down targets in the air, reaching very high speeds in little time.

How are airplanes made? 

The raw material for aircraft must be rigid, strong, corrosion-resistant, and light-weight. Most aircraft are made from titanium, steel, aluminum, and composites (often including polymers and carbon fiber).

Engineers determine what materials an airplane will be built from by taking a set of factors into account, including the dimensions, the purpose, and so on. An aircraft’s purpose especially shapes the frame and the body. Most of the old commercial airplanes were primarily made of aluminum, and newer ones are made of composite materials. Military aircraft may use a light alloy, such as titanium.

Why do planes fly?

Their operating principle is based on the aerodynamic force generated on the wings in an upward direction, called lift. This is caused by the pressure difference between the top and bottom of the wing.

The higher a plane flies, the faster it will go. This is because air becomes less dense at higher altitudes and generates less aerodynamic drag. This can also be useful to avoid turbulence and save fuel.

How high do planes fly?

The altitude at which an aircraft travels depends on several factors, such as the type of aircraft, the distance between the points of departure and arrival, wind direction, and the aircraft’s certification for RVSM (Reduced Vertical Separation Minimum) operations.

Most commercial airliners have an absolute flight ceiling of around 40,000 feet (13,000 meters), while some jets can reach 52,000 feet (15,850 meters). The upper limit for military aviation today is 82,000 feet (25,000 meters).

What fuel do planes use?

There are currently four types of jet fuel:

1. Jet A-1 or jet fuel (kerosene): this is used in turbine engines. This is subject to internationally standardized, comprehensive quality specifications to meet the high demands of the aircraft engines that use it.
2. Jet B (a mix of kerosene and gasoline): this is used in military aircraft. The mixture contains approximately 65% gasoline and 35% kerosene, and it is used in regions with especially low temperatures. This is because it is more flammable (flashpoint of 20°C and a freezing point as low as -72°C).
3. Avgas, or aviation gasoline, is only used in older piston engines found in sport aircraft and small private aircraft that require high-octane leaded fuel. Avgas is expensive, which is why diesel and kerosene are used more and more. The rise in prices is a result of the low production volume, the long supply routes, and complex quality controls.
4. Biokerosene: this is a renewable alternative made from algae, jatropha oil, etc. The aviation industry has been testing it for years on numerous flights. 

Fun facts about airplanes

• On their first powered flight, the Wright brothers, the pioneers of aviation, covered a distance of just over 10 meters.
• The shortest flight in the world lasts 27 seconds. This is a route between the islands of Westray and Papa Westray, operated by the Scottish regional airline Loganair.
• The longest non-stop flight in existence lasts 15 hours and 25 minutes, spanning the 13,800 kilometers between Sydney (Australia) and Dallas (the US).
• Spanish passengers have up to 10 years to file a complaint.
• The largest aircraft in existence today is the Antonov AN-225′, coming in at 88 meters long. It was used to transport the Buran space shuttle. The smallest aircraft is the CriCri, with a wingspan of 4.9 meters.
• On any Friday afternoon in July and August, there could be between 16,000 and 20,000 planes in the air.
• The average delay time at European airports is 30 minutes.
• The numbers 13, 17, and 666 are not used for airports or airplanes to avoid any superstition.
• The black box on aircraft is actually red so that it is more visible. 
• The highest airport is Daocheng Yading (China), at 4,410 meters above sea level, and the lowest is Amsterdam-Schiphol (Holland), at 3 meters below sea level.
• The runway at Gibraltar’s airport crosses a public road, which is blocked off when a plane is about to land.