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Wake Separation	Wake separation is the minimum distance air traffic control enforces between aircraft to prevent wake turbulence encounters. Large aircraft generate stronger wakes, requiring greater separation distances for following aircraft. ATC categorizes aircraft by weight class and applies specific separation standards to reduce the risk of turbulence-induced loss of control.
Wake Turbulence	Wake turbulence is caused by the vortices generated from an aircraft’s wingtips during flight. It can be hazardous to smaller aircraft flying behind larger ones, leading to loss of control or structural damage. Air traffic controllers provide separation between aircraft to minimize the effects, and pilots use techniques such as staying above a preceding aircraft’s glide path to avoid turbulence.
Warranted Fatigue Life	Warranted fatigue life refers to the manufacturer’s estimated lifespan of aircraft components before requiring mandatory inspections or replacements. This is determined through extensive testing and engineering data to ensure structural integrity and prevent catastrophic failures due to metal fatigue.
Waypoint	A waypoint is a defined geographical location used in navigation, typically designated by GPS coordinates. Pilots use waypoints for flight planning and route tracking. In modern aviation, waypoints help create direct, fuel-efficient paths between destinations. They are often named using five-letter codes (e.g., “DAGGA” or “SAVEE”) and are critical components of RNAV (Area Navigation) and instrument flight routes.
Weather Deviation	Weather deviation is a flight path alteration due to severe weather, requiring ATC coordination. Pilots may request deviations to avoid thunderstorms, turbulence, or icing conditions. ATC assists in rerouting to ensure safe separation from other aircraft. Advanced weather radar and predictive meteorological models help pilots anticipate and manage deviations, ensuring minimal disruption to flight schedules and passenger safety.
Weather Minimums	Weather minimums define the lowest permissible visibility and cloud clearance for flight operations. These minimums vary based on flight rules (VFR or IFR), airport equipment, and aircraft capabilities. Pilots must adhere to weather minimums to ensure safe departures, en-route navigation, and landings, especially in challenging conditions.
Weather Radar	Weather radar is an onboard system that detects precipitation, turbulence, and storm intensity by transmitting radio waves and analyzing their reflections. It allows pilots to avoid hazardous weather conditions such as thunderstorms and heavy rainfall. Modern weather radars use Doppler technology to measure wind speed and direction, providing advanced warnings about potential wind shear or microbursts.
Weight and Balance	Weight and balance refer to the distribution of an aircraft’s weight to maintain stability and control. Pilots and dispatchers calculate weight and balance before each flight to ensure the center of gravity remains within safe limits. Incorrect loading can lead to control issues, reduced performance, or even structural failure during flight, making it a crucial pre-flight procedure.
Weight Shift Control	Weight shift control is a flight control technique used in ultralight and hang-glider aircraft, where pilots shift their body weight to maneuver instead of using conventional control surfaces. This system relies on the aircraft's center of gravity for directional control, making it simple yet highly effective for powered parachutes and trikes. It enhances responsiveness, particularly in light sport aviation.
Weld Line	A weld line is a joint where two metal surfaces are fused together during aircraft construction or repair. High-quality welding ensures structural durability, especially in aircraft engines, fuselage panels, and landing gear assemblies. Welds must withstand extreme temperatures, vibrations, and pressures encountered during flight, requiring rigorous quality control and non-destructive testing methods.
Wet Lease	A wet lease is an aircraft leasing agreement where the lessor provides the aircraft, crew, maintenance, and insurance. Airlines use wet leases for temporary capacity increases, covering seasonal demand or aircraft maintenance downtime. Unlike dry leases, which exclude crew, wet leases allow rapid deployment with minimal preparation.
Wet Runway	A wet runway is one covered with visible moisture, such as rain or melting snow, affecting braking efficiency and increasing stopping distances. Pilots use specialized landing techniques, including auto-braking and reverse thrust, to compensate for reduced friction. Regulations define how wet conditions impact aircraft performance calculations, ensuring safe landings and takeoffs.
Wet Start	A wet start occurs when excess fuel ignites in a jet engine during startup, producing abnormal flames. This may be caused by a fuel valve malfunction, improper ignition timing, or pilot error. Wet starts can lead to engine damage or fire hazards if not managed correctly. Modern engine monitoring systems detect and prevent wet starts, improving operational safety and efficiency.
Wheels-Up Time (WUT)	Wheels-up time is the scheduled time an aircraft is expected to take off, often assigned by air traffic control during busy operations. Adherence to wheels-up time helps manage airspace congestion and coordinate departures. Airlines use wheels-up times to optimize scheduling and fuel efficiency, ensuring smooth operations in high-traffic airports.
White Noise	White noise is used in aviation headsets to mask ambient cockpit noise, improving pilot communication. By generating a consistent sound frequency, white noise reduces distractions caused by engine hum, wind turbulence, and avionics systems. This enhances voice clarity over radio transmissions and protects pilots’ hearing by minimizing long-term exposure to high-decibel environments common in commercial and military aviation.
Widebody Aircraft	A widebody aircraft has a fuselage large enough to accommodate two passenger aisles. These aircraft, such as the Boeing 777 and Airbus A350, are used for long-haul flights and carry more passengers and cargo than narrowbody aircraft. Widebody planes provide increased comfort, advanced in-flight entertainment systems, and better fuel efficiency for transcontinental and international routes.
Windshear	Windshear is a sudden change in wind speed or direction over a short distance, often occurring during takeoff and landing. Severe windshear can lead to rapid loss of altitude and airspeed, making it one of aviation’s most dangerous weather phenomena. Pilots are trained to recognize windshear through onboard alerts and take corrective action to maintain control.
Winglet<	A winglet is an aerodynamic extension at the tip of an aircraft’s wing, designed to reduce drag and improve fuel efficiency. Winglets minimize vortex formation, which decreases turbulence and increases lift. Many modern commercial aircraft, such as the Boeing 737 MAX and Airbus A320neo, incorporate winglets to improve range and lower operational costs.
Wing Loading	Wing loading is the ratio of an aircraft’s weight to its wing area, measured in pounds per square foot. It affects maneuverability, stall speed, and takeoff performance. Lower wing loading allows for better lift and slower stall speeds, whereas high wing loading results in higher takeoff and landing speeds, making it a crucial factor in aircraft design.
Wing Sweep	Wing sweep refers to the backward or forward angle of an aircraft’s wings, affecting aerodynamics and speed. Most jet aircraft have swept-back wings to reduce drag at high speeds. Supersonic aircraft, such as the Concorde, use highly swept wings to minimize shock waves and maintain stability at transonic and supersonic speeds.
Windsock	A windsock is a cone-shaped fabric indicator used at airports to show wind direction and approximate speed. Positioned near runways, it provides pilots with a quick visual reference for landing and takeoff decisions. The windsock’s angle corresponds to wind strength, helping pilots determine crosswind conditions and approach adjustments.
Wind Tunnel	A wind tunnel is a testing facility that simulates airflows over aircraft designs to evaluate aerodynamic performance. Engineers use wind tunnels to test wing shapes, control surfaces, and drag reduction techniques. These tests help improve aircraft efficiency, safety, and fuel economy by refining aerodynamic properties before full-scale production.
Wing Fence	A wing fence is a vertical barrier installed on a wing to control airflow and reduce spanwise movement of air, improving stability and stall characteristics. Originally developed for early swept-wing designs, wing fences are still used in some modern aircraft to enhance control during slow-speed flight and approach.
Wind Correction Angle (WCA)	Wind correction angle is the heading adjustment a pilot makes to compensate for crosswinds, ensuring an aircraft stays on its intended course. Calculating WCA is essential for accurate navigation, particularly in strong wind conditions where uncorrected drift can lead to significant deviations from planned routes.
Wing Box	The wing box is the structural core of an aircraft’s wing, housing critical components like fuel tanks, landing gear mounts, and internal supports. It provides strength and distributes aerodynamic loads, ensuring the aircraft withstands various stresses encountered in flight.
Wing Flex	Wing flex refers to the natural bending of an aircraft’s wings during flight due to aerodynamic forces. Modern composite wings, such as those on the Boeing 787, are designed to flex significantly, improving ride comfort and structural longevity. This flexibility absorbs turbulence-induced stress, reducing fatigue on the airframe while enhancing overall aerodynamic efficiency and passenger comfort.
Wind Gradient	Wind gradient refers to changes in wind speed and direction with altitude, affecting takeoff and landing performance. A strong wind gradient near the surface can cause rapid airspeed fluctuations, making aircraft handling more challenging. Pilots adjust for wind gradient effects by modifying approach speeds and being prepared for sudden wind shear events that could impact aircraft stability and descent control.
Wing Root	The wing root is the section where the wing attaches to the fuselage, playing a crucial role in aerodynamics and load distribution. This structurally reinforced area houses critical components such as fuel tanks, landing gear attachments, and electrical wiring. Engineers design wing roots to handle high stress, as they bear the forces generated by lift, weight, and flight maneuvers.
Wingover	A wingover is an aerobatic maneuver where the aircraft turns 180 degrees at the top of a steep climb. The pilot initiates a rapid climb, reduces power, and applies rudder and aileron input to pivot the aircraft over the top before descending in the opposite direction. Wingovers are used in aerial displays, military flight tactics, and advanced pilot training.
Wire Strike Protection	Wire strike protection systems are installed on helicopters to reduce the risk of collisions with power lines, enhancing low-altitude safety. These systems include cutting devices mounted on the fuselage and rotor mast, designed to sever wires before they entangle the aircraft. Wire strike prevention training and advanced obstacle-detection sensors further mitigate the hazards associated with flying near power lines.
Wright-Patterson AFB Hangar 4	Wright-Patterson AFB Hangar 18 is reportedly storing UFO wreckage and alien bodies from the 1947 Roswell crash Among other things). The base is one of the documented destinations of JANET Airlines. UFO researcher Robert Spencer Carr popularized the theory, but the U.S. Air Force denies its existence. Despite no evidence, the legend persists in pop culture, inspiring films and music, fueling conspiracy theories of government cover-ups.