N November

NATCA (National Air Traffic Controllers Association) - Labor union representing air traffic controllers, engineers, and related safety professionals

National Aeronautics and Space Administration (NASA) - In 1958, NASA was created as a government agency to replace NACA. NASA's charter is to expand frontiers in air and space, to inspire and serve America, and to benefit the quality of life on Earth.

National Airspace System - The common network of US airspace; air navigation facilities, equipment and services, airports or landing areas; aeronautical charts, information and services; rules, regulations and procedures, technical information, and human resources and material. Included are system components shared jointly with the military.

national flights - Flights which depart and arrive within the United States.

National Weather Service (NWS) - A primary branch of the National Oceanic and Atmospheric Administration, it is responsible for all aspects of observing and forecasting atmospheric conditions and their consequences, including severe weather and flood warnings.

nautical miles - A unit of length used in sea and air navigation, based on the length of one minute of arc of a great circle, especially an international and U.S. unit equal to 1852

navigation - Plotting the most direct course to a given destination, flying the route as plotted and arriving at the destination within the stated time parameters.

navigational fix - A geographical position determined by visual reference to the surface, by reference to one or more radio NAVAIDS, by celestial plotting or by another navigational device. Or, a certain point through which an aircraft is directed to fly by an air traffic controller.

NDBs (Non-Directional Beacons) - A medium-frequency navigational aid which transmits non-directional signals, superimposed with a Morse-code identifier and received by an aircraft's ADF.

negative - Aviation term for "no"; expressing or implying a denial or refusal; lacking in positive character or quality; lacking evidence or affirmation.

nimbostratus - A principal cloud type, gray colored, often dark, the appearance of which is rendered diffuse by more or less continuously falling rain or snow, which in most cases reaches the ground.

niner - The International Phonetic Numeral for the number "nine".

nitrogen oxides - NO and NO2: gaseous pollutants produced by the combustion of fuels.

nm - Newton-meter: a unit of energy or work also known as a joule(J). It is the work done when the force of one unit acts through the distance of one meter.

nmph - Newton-meter per hour: a unit of power. In aeronautical terms, power is the product of thrust times velocity. The power of aircraft engines varies widely with their velocities.

noise abatement procedures - A course of action taken in order to reduce aircraft engine noise over populated areas.

non-towered airport - An airport not directed by air traffic control; pilots fly into and out of these airport using standard operating procedures to avoid one another.

nose gear - The landing gear nearest the nose of the aircraft; usually under the cockpit.

NOTAM (Notice to Airmen) - A notice containing information concerning establishment, condition, or any component in the NAS of which the timely knowledge is essential to personnel concerned with flight operations. When the problem no longer exists, or it is published in other applicable documents, it will be discontinued as a NOTAM.

November - Designator for the letter "N" in the International Phonetic Alphabet.