nano. The metric prefix meaning one billionth (1 x 10-9) of a unit.
nanovoltmeter. An extremely sensitive voltmeter that can measure voltages as low as one nanovolt (one thousandth of a microvolt).
nap (fabric). The ends of the fibers in a fabric. Certain steps in the finishing of fabric materials cause the nap to stick up. This is called “raising the nap.” When an aircraft structure is covered with cotton or linen fabric, the first coat of dope raises the nap. This nap must be carefully removed by sanding to get a smooth finish.
naphtha (aliphatic naphtha). A petroleum product whose boiling point is between that of gasoline and kerosine. Aliphatic naphtha is used as a cleaning solvent and as an ingredient in certain finishing materials.
naphtha (aromatic naphtha). A solvent produced from coal tar. Aromatic naphtha is used as a blending agent for changing the performance characteristics of gasoline. It has a softening effect on rubber goods, such as flexible hoses and diaphragms used in pumps and fuel metering components.
narrowing grinding (reciprocating engine valve seat grinding). The grinding away of part of the top edge of the valve seat in the cylinder of a reciprocating engine. Narrowing decreases the contact area between the valve face and the valve seat.
NASA. National Aeronautics and Space Administration. See NACA.
NAS specifications (National Aircraft Standards). Specifications established by the National Aircraft Standards Committee for the design and construction of components. Parts conforming to these standards are identified with a number preceded by the initials NAS.
NAS (national airspace system). The common network of U.S. airspace; air navigation facilities, equipment and services, airports or landing areas; aeronautical charts, information and services; rules, regulations and procedures, technical information, and manpower and material.
Included are system components shared jointly with the military.
NAS stage A (air traffic control). The enroute ATC system’s radar, computers and computer programs, controller plan view displays (PVDs/radar scopes), input/output devices, and the related communications equipment which are integrated to form the heart of the automated IFR air traffic control system.
This equipment performs flight data processing (FDP) and radar data processing (RDP). It interfaces with automated terminal systems and is used in the control of enroute IFR aircraft.
National Flight Data Center. See NFDC.
National Flight Data Digest (air traffic control publication). A daily (except weekends and Federal holidays) publication of flight information appropriate to aeronautical charts, aeronautical publications, Notices to Airmen, or other media, serving the purpose of providing operational flight data essential to safe and efficient aircraft operations.