United States Air Force

The United States Air Force (USAF) is the aerial warfare service branch of the United States Armed Forces and one of the seven American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on 18 September 1947 under the National Security Act of 1947. It is the most recent branch of the U.S. military to be formed, and is the largest and one of the world's most technologically advanced air forces. The USAF articulates its core functions as Nuclear Deterrence Operations, Special Operations, Air Superiority, Global Integrated ISR, Space Superiority, Command and Control, Cyberspace Superiority, Personnel Recovery, Global Precision Attack, Building Partnerships, Rapid Global Mobility and Agile Combat Support.

The U.S. Air Force is a military service organized within the Department of the Air Force, one of the three military departments of the Department of Defense. The Air Force is headed by the civilian Secretary of the Air Force, who reports to the Secretary of Defense, and is appointed by the President with Senate confirmation. The highest-ranking military officer in the Department of the Air Force is the Chief of Staff of the Air Force, who exercises supervision over Air Force units, and serves as a member of the Joint Chiefs of Staff. Air Force combat and mobility forces are assigned, as directed by the Secretary of Defense, to the Combatant Commanders, and neither the Secretary of the Air Force nor the Chief of Staff have operational command authority over them.

Air force

An air force, also known in some countries as an air army, is in the broadest sense, the national military organization that primarily conducts aerial warfare. More specifically, it is the branch of a nation's armed services that is responsible for aerial warfare as distinct from an army, navy, or a marine corps. Typically, air forces are responsible for gaining control of the air, carrying out strategic and tactical bombing missions, and providing support to land and naval forces.

The term "air force" may also refer to a tactical air force or numbered air force, which is an operational formation either within a national air force or comprising several air components from allied nations. Air forces typically consist of a combination of fighters, bombers, helicopters, transport planes and other aircraft.

Many air forces are also responsible for operations of the military space, intercontinental ballistic missiles (ICBM), and communications equipment. Some air forces may command and control other air defence assets such as anti-aircraft artillery, surface-to-air missiles, or anti-ballistic missile warning networks and defensive systems. Some nations, principally Russia, the former Soviet Union and countries who modelled their militaries along Soviet lines, have an air defence force which is organizationally separate from their air force.

US Airways

US Airways was a major American airline that ceased operations on October 17, 2015 after merging with American Airlines. It operated an extensive international and domestic network, with 193 destinations in 24 countries in North America, South America, Europe and the Middle East. The airline was an affiliate member of Oneworld and utilized a fleet of 343 mainline jet aircraft, as well as 278 regional jet and turbo-prop aircraft operated by contract and subsidiary airlines under the name US Airways Express.

The carrier operated the US Airways Shuttle, a US Airways brand which provided hourly service between Boston, New York City and Washington, D.C. As of October 2013, US Airways employed 32,312 people worldwide and operated 3,028 daily flights (1,241 US Airways Mainline, 1,790 US Airways Express) Roughly 60% of US Airways flights were operated by US Airways Express.

In 1979, after passage of the Airline Deregulation Act, Allegheny Airlines changed its name to USAir and began seeking to expand its operations. A decade later, it had acquired Piedmont Airlines and Pacific Southwest Airlines, and was one of the U.S.'s seven remaining transcontinental legacy carriers. In 2005, America West Airlines carried out a reverse merger, acquiring the assets and branding of the larger US Airways while putting the America West leadership team largely in charge of the merged airline.

Force

In physics, a force is any interaction that, when unopposed, will change the motion of an object. In other words, a force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate. Force can also be described by intuitive concepts such as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newtons and represented by the symbol F.

The original form of Newton's second law states that the net force acting upon an object is equal to the rate at which its momentum changes with time. If the mass of the object is constant, this law implies that the acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional to the mass of the object

Related concepts to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque, which produces changes in rotational speed of an object. In an extended body, each part usually applies forces on the adjacent parts; the distribution of such forces through the body is the so-called mechanical stress. Pressure is a simple type of stress. Stress usually causes deformation of solid materials, or flow in fluids.

United States

Coordinates: 40°N 100°W / 40°N 100°W / 40; -100

The United States of America (USA), commonly referred to as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major territories and various possessions. The 48 contiguous states and Washington, D.C., are in central North America between Canada and Mexico. The state of Alaska is in the northwestern part of North America and the state of Hawaii is an archipelago in the mid-Pacific. The territories are scattered about the Pacific Ocean and the Caribbean Sea. At 3.8 million square miles (9.842 million km²) and with over 320 million people, the country is the world's third or fourth-largest by total area and the third most populous. It is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many countries. The geography and climate of the United States are also extremely diverse, and the country is home to a wide variety of wildlife.