Air travel

Air travel are separated into two general classifications: national/domestic and international flights. Flights from one point to another within the same country are domestic flights. Flights from a point in one country to a point within a different country are international flights. Travelers can use domestic or international flights in either private or public travel.

Travel class on an airplane is usually split into a two, three or four class model service. U.S. domestic flights usually have two classes: economy class and a domestic first class partitioned into cabins. International flights may have up to four classes: economy class; premium economy; business class or club class; and first class.

Most air travel starts and ends at a commercial airport. The typical procedure is check-in; border control; airport security baggage and passenger check before entering the gate; boarding; flying; and pick-up of luggage and – limited to international flights – another border control at the host country's border.

For longer journeys, air travel may consist of several flights with a layover in between. The number of layovers often depends on the number of hub airports the journey is routed through.

Airlines rely either on the point-to-point model or the spoke-and-hub model to operate flights in between airports. The point-to-point model, often used by low-cost carriers such as Southwest,[4] relies on scheduling flights directly between destination airports. The spoke-and-hub model, used by carriers such as American[5] and Delta,[6] relies on scheduling flights to and from hub airports. The hub-and-spoke model allows airlines to connect more destinations and provide more frequent routes, while the point-to-point system allows airlines to avoid layovers and have more cost effective operations.[7]

Part of a series on
Pollution
Air pollution from a factory
Air Acid rain Air quality index Atmospheric dispersion modeling Chlorofluorocarbon Exhaust gas Haze Indoor air Internal combustion engine Global dimming Global distillation Ozone depletion Particulates Persistent organic pollutant Smog Aerosol Soot Volatile organic compound
Biological Biological hazard Genetic Introduced species (Invasive species)
Digital Information
Electromagnetic Light Ecological Overillumination Radio spectrum
Natural Ozone Radium and radon in the environment Volcanic ash Wildfire
Noise Transportation Land Water Air Rail Sustainable transport Urban Sonar Marine mammals and sonar Industrial Military Abstract Noise control
Radiation Actinides Bioremediation Depleted uranium Nuclear fission Nuclear fallout Plutonium Poisoning Radioactivity Uranium Electromagnetic radiation and health Radioactive waste
Soil Agricultural Herbicides Manure waste Pesticides Land degradation Bioremediation Defecation Electrical resistance heating Soil guideline values Phytoremediation
Solid waste Biodegradable waste Brown waste Electronic waste Battery recycling Food waste Green waste Hazardous waste Biomedical waste Chemical waste Construction waste Lead poisoning Mercury poisoning Toxic waste International waste Industrial waste Lead smelting Litter Mining Coal mining Gold mining Surface mining Deep sea mining Mining waste Uranium mining Municipal solid waste Garbage Nanomaterials Plastic Microplastics Packaging waste Post-consumer waste Waste management Landfill Thermal treatment
Space Satellite
Thermal Urban heat island
Visual Air travel Advertising clutter Overhead power lines Traffic signs Vandalism
War Chemical warfare Herbicidal warfare (Agent Orange) Nuclear holocaust (Nuclear fallout - nuclear famine - nuclear winter) Scorched earth Unexploded ordnance War and environmental law
Water Agricultural wastewater Biosolids Diseases Eutrophication Firewater Freshwater Groundwater Hypoxia Industrial wastewater Marine debris Monitoring Nonpoint source see Misc section Nutrient Ocean acidification Oil spill Pharmaceuticals Freshwater salinization Septic tanks Sewage Septic tanks Pit latrine Shipping Sludge Stagnation Sulfur water Surface runoff Turbidity Urban runoff Water quality Wastewater
Misc Area source Debris Garbology Legacy pollution Midden Point source Waste Lists Diseases Law by country Most polluted cities Least polluted cities by PM2.5 Treaties Categories By country
Environment portal  Ecology portal

Modern aircraft consume less fuel per person and mile traveled than cars when fully booked.[8] However, the distances traveled are often significantly larger and will not replace car travel but instead add to it, and not every flight is booked out.

Instead, the scheduled flights are predominant, resulting in a far worse fuel efficiency.[9][10][11] According to the ATAG, flights produced 781 million tonnes (769 million long tons) of the greenhouse gas CO₂ in 2015 globally, as compared to an estimated total of 36 billion tonnes (35 billion long tons) anthropogenic CO₂.[12] Carbon offset is often proposed as solution to mitigate the CO₂ emissions of flying. There are many NGOs that offer to compensate CO₂ emissions by advancing clean renewable energy, reducing energy consumption and capturing already released carbon in trees or other plants.[13] However, carbon offsetting is a very controversial topic as it only tries to mitigate what has already been emitted.[14]

Modern air travel is significantly safer than road travel.[15] In 2008 in the United States, there were 1.27 fatalities per 100 million road vehicle miles, compared to no fatalities and almost zero accidents per million flying miles.[15] There were more than five million driving accidents, compared to 20 accidents in flying.[15] Travelers may perceive planes to be more dangerous as they do not allow individual control and because plane crashes are more catastrophic events (the availability bias).[15]

Deep vein thrombosis (DVT) is the third-most common vascular disease, next to stroke and heart attack. It is estimated that DVT affects one in 5,000 travelers on long flights.[16][17] Risk increases with exposure to more flights within a short time frame and with increasing duration of flights.[17]

During flight, the aircraft cabin pressure is usually maintained at the equivalent of 6,000–8,000 ft (1,800–2,400 m) above sea level. Most healthy travelers will not notice any effects. However, for travelers with cardiopulmonary diseases (especially those who normally require supplemental oxygen), cerebrovascular disease, anemia, or sickle cell disease, conditions in an aircraft can exacerbate underlying medical conditions. Aircraft cabin air is typically dry, usually 10%–20% humidity, which can cause dryness of the mucous membranes of the eyes and airways.[18]

Wikimedia Commons has media related to Air transport.

• http://openflights.org/ a tool that lets you map your flights around the world
• https://aerogon.aero/ air trafficking management