Order 7110.65P, Air Traffic Control, with changes

2/19/04Pilot/Controller GlossaryWWA−(See AIRMET.)(See WEATHER ADVISORY.)WAAS−(See WIDE-AREA AUGMENTATION SYSTEM.)WAKE TURBULENCE− Phenomena resulting fromthe passage of an aircraft through the atmosphere.The term includes vortices, thrust stream turbulence,jet blast, jet wash, propeller wash, and rotor washboth on the ground and in the air.(See AIRCRAFT CLASSES.)(See JET BLAST.)(See VORTICES.)(Refer to AIM.)WARNING AREA−(See SPECIAL USE AIRSPACE.)WAYPOINT− A predetermined geographical positionused for route/instrument approach definition,progress reports, published VFR routes, visualreporting points or points for transitioning and/orcircumnavigating controlled and/or special use airspace,that is defined relative to a VORTAC stationor in terms of latitude/longitude coordinates.WEATHER ADVISORY− In aviation weather forecastpractice, an expression of hazardous weatherconditions not predicted in the area forecast, as theyaffect the operation of air traffic and as prepared bythe NWS.(See AIRMET.)(See SIGMET.)WHEN ABLE− When used in conjunction with ATCinstructions, gives the pilot the latitude to delaycompliance until a condition or event has beenreconciled. Unlike “pilot discretion,” when instructionsare prefaced “when able,” the pilot is expectedto seek the first opportunity to comply. Once amaneuver has been initiated, the pilot is expected tocontinue until the specifications of the instructionshave been met. “When able,” should not be usedwhen expeditious compliance is required.WIDE-AREA AUGMENTATION SYSTEM(WAAS)− The WAAS is a satellite navigation systemconsisting of the equipment and software whichaugments the GPS Standard Positioning Service(SPS). The WAAS provides enhanced integrity,accuracy, availability, and continuity over and aboveGPS SPS. The differential correction function providesimproved accuracy required for precisionapproach.WILCO− I have received your message, understandit, and will comply with it.WIND GRID DISPLAY− A display that presents thelatest forecasted wind data overlaid on a map of theARTCC area. Wind data is automatically entered andupdated periodically by transmissions from theNational Weather Service. Winds at specific altitudes,along with temperatures and air pressure can beviewed.WIND SHEAR− A change in wind speed and/or winddirection in a short distance resulting in a tearing orshearing effect. It can exist in a horizontal or verticaldirection and occasionally in both.WING TIP VORTICES−(See VORTICES.)WORDS TWICE−a. As a request: “Communication is difficult.Please say every phrase twice.”b. As information: “Since communications aredifficult, every phrase in this message will be spokentwice.”WORLD AERONAUTICAL CHARTS−(See AERONAUTICAL CHART.)WS−(See SIGMET.)(See WEATHER ADVISORY.)WST−(See CONVECTIVE SIGMET.)(See WEATHER ADVISORY.)PCG W−1