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Nacelle	A nacelle is an aerodynamic housing that encloses an aircraft engine, typically found on the wings or fuselage. It protects the engine, improves airflow, and reduces drag. Nacelles also contain essential systems such as engine mounts, cooling ducts, and fire suppression mechanisms.
Nano Air Vehicle (NAV)	A NAV is a small, lightweight unmanned aircraft system designed for surveillance, reconnaissance, and research. These ultra-compact drones can hover, maneuver in confined spaces, and are often used for military or scientific applications.
National Airspace System (NAS)	The NAS encompasses all controlled and uncontrolled airspace, airports, navigation aids, and air traffic control facilities within a country’s jurisdiction. It ensures safe and efficient flight operations for commercial, military, and general aviation.
National Transportation Safety Board (NTSB)	The National Transportation Safety Board (NTSB) operating out of 490 L'Enfant Plaza, SW, Washington, DC 20594 , (202) 314-6000, is an independent federal agency responsible for investigating all U.S. civil aviation accidents and major incidents in other transportation modes—rail, highway, marine, pipeline, transit, and commercial space. It determines probable causes, issues safety recommendations, conducts research, and supports victims’ families. The NTSB also serves as an appellate authority for FAA and Coast Guard enforcement actions and adjudicates appeals of FAA civil penalties.
Nautical Mile (NM)	A nautical mile is a unit of measurement used in aviation and maritime navigation. It equals 1.852 kilometers or 1.151 miles. Nautical miles are based on the Earth's circumference, making them ideal for calculating distances over water and air travel.
Navigation Aid (NAVAID)	A NAVAID is any visual or electronic system that assists pilots in navigating. Common types include VOR (Very High-Frequency Omnidirectional Range), NDB (Non-Directional Beacon), and GPS-based aids, all of which provide location and directional guidance.
Navigational Chart	A navigational chart is a specialized map used by pilots for flight planning and navigation. It includes information on airways, airports, terrain, and NAVAIDs, ensuring safe route selection and situational awareness.
Navigation Fix	A navigation fix is a precise geographical point used in flight planning and navigation. Fixes are established using radio beacons, GPS, or intersections of navigation aids.
Navigation Lights	Aircraft navigation lights include red (left wing), green (right wing), and white (tail) lights. They help identify an aircraft’s orientation and position during nighttime operations, enhancing safety by preventing midair collisions.
Navigational Redundancy	Navigational redundancy refers to having multiple backup systems for navigation to prevent total system failure. Modern aircraft use GPS, inertial navigation, and radio beacons to ensure reliable guidance.
Negative G-Force	Negative G-force occurs when an aircraft accelerates downward faster than gravity, causing occupants to experience a sensation of weightlessness or being lifted from their seats. Extreme negative Gs can cause discomfort and disorientation.
No-Engine Landing	A no-engine landing, also called a forced landing, occurs when an aircraft loses engine power and must glide to the ground safely. Pilots train for such scenarios to ensure controlled landings without power.
No-Flap Landing	A no-flap landing is an approach performed without extending the wing flaps. This is necessary if there is a flap malfunction or failure. The aircraft must land at a higher speed to compensate for the lack of additional lift and drag.
Noise Abatement Procedures	Noise abatement procedures are flight techniques and airport regulations designed to minimize aircraft noise impact on surrounding communities. These include specific climb angles, reduced power takeoffs, and noise-friendly approach paths.
Non-Directional Beacon (NDB)	An NDB is a low-frequency radio transmitter used for navigation. Pilots use ADF (Automatic Direction Finder) instruments to determine their position relative to an NDB, guiding them toward a destination.
Non-Stop Flight	A non-stop flight is a direct flight between two points without layovers or refueling stops. Airlines prioritize non-stop routes to reduce travel time and improve passenger convenience.
Non-Precision Approach	A non-precision approach is an instrument landing approach without vertical guidance. Unlike an ILS, it only provides lateral guidance using systems like VOR, NDB, or GPS, requiring pilots to rely on altitude steps for descent.
No-Transgression Zone (NTZ)	The NTZ is a restricted airspace area between parallel approach paths at busy airports. It prevents aircraft from deviating into opposing traffic during simultaneous instrument approaches.
Normal Category Aircraft	Aircraft classified under the normal category are designed for non-aerobatic operations, carrying up to nine passengers and having a maximum takeoff weight of 12,500 pounds. These aircraft are used for private, corporate, and flight training purposes.
North Atlantic Tracks (NATs)	NATs are predefined, high-altitude routes used for transatlantic flights between North America and Europe. These tracks change daily based on wind patterns to optimize efficiency and fuel consumption.
Nose Gear	The nose gear is part of the aircraft’s landing gear located under the forward fuselage. It supports the aircraft’s nose and is steerable, enabling pilots to maneuver while taxiing.
Nose High Attitude	A nose-high attitude occurs when an aircraft’s pitch angle is excessively upward relative to the horizon. This can lead to a stall if the airspeed drops too low.
Nose Low Attitude	A nose-low attitude occurs when an aircraft’s pitch angle is excessively downward relative to the horizon. This may lead to an overspeed condition, requiring pilots to level off and reduce throttle.
Nose Wheel Steering (NWS)	NWS is a system that allows pilots to control the aircraft’s nose wheel direction while taxiing. It provides precise ground handling and enhances maneuverability on runways and taxiways.
NOTAM (Notice to Airmen)	A NOTAM is an advisory issued to pilots and air traffic personnel about temporary flight restrictions, airport closures, navigation hazards, or other critical updates affecting flight safety.
Nuclear-Powered Aircraft Concept	Experimental designs have explored nuclear-powered aircraft capable of long-endurance flights without refueling. While never operationalized, research in this field has influenced nuclear propulsion technology.
Number Two Engine	On multi-engine aircraft, the number two engine is typically the second engine from the left when facing forward. Engine numbering helps pilots and mechanics identify and manage engine-specific operations.
Nurse Tank (Aerial Refueling)	A nurse tank is an auxiliary fuel tank used in aerial refueling operations. It allows aircraft to extend range and endurance by transferring fuel mid-flight, commonly used in military aviation.
Nutrient Supply for Space Flight	Nutrient supply systems are essential for long-duration space flights and high-altitude aircraft missions, ensuring that pilots and astronauts receive adequate hydration and nutrition.
Nyquist Filter (Avionics Signal Processing)	A Nyquist filter is used in avionics to process digital communication signals, reducing noise and improving data accuracy for aircraft systems such as radar and flight computers.