Transporters

Fixed-wing aircraft include a large range of craft from small training and recreational aircraft to large airliners and military cargo aircraft. Some aircraft use fixed wings to provide lift only part of the time and may or may not be referred to as fixed-wing.

The word also embraces aircraft with folding or removable wings that are intended to fold when on the ground. This is usually to ease storage or facilitate transport on, for example, a vehicle trailer or the powered lift connecting the hangar deck of an aircraft carrier to its flight deck. It also embraces "variable geometry" aircraft, such as the General Dynamics F-111, Grumman F-14 Tomcat and the Panavia Tornado, which can vary the sweep angle of their wings during flight. There are also rare examples of aircraft which can vary the angle of incidence of their wings in flight, such the F-8 Crusader, which are also considered to be "fixed-wing".

An F-16 Fighting Falcon, an American military fixed-wing aircraft

Two necessities for all fixed-wing aircraft (as well as rotary-wing aircraft) are air flow over the wings for lifting of the aircraft, and an open area for landing. The majority of aircraft, however, also need an airport with the infrastructure to receive maintenance, restocking, refueling and for the loading and unloading of crew, cargo and/or passengers. While the vast majority of aircraft land and take off on land, some are capable of take off and landing on ice, aircraft carriers, snow, and calm water.

The aircraft is the second fastest method of transport, after the rocket. Commercial jet aircraft can reach up to 900 km/h. Single-engined aircraft are capable of reaching 175 km/h or more at cruise speed. Supersonic aircraft (military, research and a few private aircraft) can reach speeds faster than sound. The speed record for a plane powered by an air-breathing engine is currently held by the experimental NASA X-43, which reached nearly ten times the speed of sound.

The biggest aircraft currently in service is Antonov An-225, while the fastest currently in production is the Mikoyan MiG-31. The biggest supersonic jet ever produced and currently in service is Tupolev-160.

The design of modern cars is typically handled by a large team of designers and engineers from many different disciplines. As part of the product development effort the team of designers will work closely with teams of design engineers responsible for all aspects of the vehicle. These engineering teams include: chassis, body and trim, powertrain, electrical and production. The design team under the leadership of the design director will typically comprise of an exterior designer, an interior designer (usually referred to as stylists), and a color and materials designer. A few other designers will be involved in detail design of both exterior and interior. For example, a designer might be tasked with designing the rear light clusters or the steering wheel. The color and materials designer will work closely with the exterior and interior designers in developing exterior color paints, interior colors, fabrics, leathers, carpet, wood trim, and so on.

In 1924 the American national automobile market began reaching saturation. To maintain unit sales, General Motors instituted annual model-year design changes (also credited to Alfred Sloan) in order to convince car owners they needed a replacement each year. Since 1935 automotive form has been driven more by consumer expectations than engineering improvement.

There have been many efforts to innovate automobile design funded by the NHTSA, including the work of the NavLab group at Carnegie Mellon University.^[17] Recent efforts include the highly publicized DARPA Grand Challenge race.^[18]

Acceleration, braking, and measures of turning or agility vary widely between different makes and models of automobile. The automotive publication industry has developed around these performance measures as a way to quantify and qualify the characteristics of a particular vehicle. See quarter mile and 0 to 60 mph.

Fuel and propulsion technologies

See also: Alternative fuel vehicle

Most automobiles in use today are propelled by gasoline (also known as petrol) or diesel internal combustion engines, which are known to cause air pollution and are also blamed for contributing to climate change and global warming.^[19] Increasing costs of oil-based fuels and tightening environmental law and restrictions on greenhouse gas emissions are propelling work on alternative power systems for automobiles. Efforts to improve or replace these technologies include hybrid vehicles, electric vehicles and hydrogen vehicles.

Diesel

Diesel engined cars have long been popular in Europe with the first models being introduced in the 1930s by Mercedes Benz and Citroen. The main benefit of Diesels are a 50% fuel burn efficiency compared with 27%^[20] in the best gasoline engines. A down side of the diesel is the presence in the exhaust gases of fine soot particulates and manufacturers are now starting to fit filters to remove these. Many diesel powered cars can also run with little or no modifications on 100% biodiesel.

Gasoline

Gasoline engines have the advantage over diesel in being lighter and able to work at higher rotational speeds and they are the usual choice for fitting in high performance sports cars. Continuous development of gasoline engines for over a hundred years has produced improvements in efficiency and reduced pollution. The carburetor was used on nearly all road car engines until the 1980s but it was long realised better control of the fuel/air mixture could be achieved with fuel injection. Indirect fuel injection was first used in aircraft engines from 1909, in racing car engines from the 1930s, and road cars from the late 1950s.^[20] Gasoline Direct Injection (GDI) is now starting to appear in production vehicles such as the 2007 BMW MINI. Exhaust gases are also cleaned up by fitting a catalytic converter into the exhaust system. Clean air legislation in many of the car industries most important markets has made both catalysts and fuel injection virtually universal fittings. Most modern gasoline engines are also capable of running with up to 15% ethanol mixed into the gasoline - older vehicles may have seals and hoses that can be harmed by ethanol. With a small amount of redesign, gasoline-powered vehicles can run on ethanol concentrations as high as 85%. 100% ethanol is used in some parts of the world (such as Brazil), but vehicles must be started on pure gasoline and switched over to ethanol once the engine is running. Most gasoline engined cars can also run on LPG with the addition of an LPG tank for fuel storage and carburetion modifications to add an LPG mixer. LPG produces fewer toxic emissions and is a popular fuel for fork lift trucks that have to operate inside buildings.