SIMULTANEOUS APPROCH TO PARALLEL RUNWAYS.

Any Airports that have 2 or more parallel runways may be authorized to simultaneous parallel approaches to maximize its capacity .

there are three classification of simultaneous parallel approaches , depending on the runway centreline separation and ATC procedures :

1- Simultaneous dependent Approaches .

2-Simultaneous independent Approaches .

3- Simultaneous close parallel precision Runway monitor ( PRM) Approaches .

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SIMULTANEOUS DEPENDENT APPROCH :

Simultaneous dependent instrument approach can be conducted with runways spaced less than 2500 feet with specific separations and threshold staggers .

ATC will applies specific minimums of diagonal separation criteria and special Wake turbulence depending on the runway separation , between aircraft on adjacent final approach courses , Aircraft will be staggered by a minimum 1 NM diagonally on final .

SIMULTANEOUS INDEPENDENT APPROACH ( mentioned on the approach chart )

A simultaneous dependent approach differs from a simultaneous independent approach in that the minimum distance between parallel runways centreline maybe less.

A staggered separation of aircraft on the adjacent final approach course is required but there is no requirement for a NO Transgression Zone (NTZ ) or final Monitor controllers.

NTZ definition :

is defined as 2000 foot wide area located equidistant between the final approach course in which flight is not allowed during the simultaneous operation . out side of the NTZ , normal operating zones( NOZ) indicate the operating zone within which aircraft remain during normal approach.

AN independent approach eliminates the need for staggered approaches and aircraft may be side by side or pass if speed are different .

As part of independent approach approval , an NTZ must be established to ensure proper flight track boundaries for all traffic .

A local controller for each runway is also required to monitor separation, track aircraft position and issue instructions to pilots of aircraft observed deviating from final approach course .

NOTE : triple simultaneous independent approaches are authorized provided the runway centrelines are separated by at least 3900 feet for straight in approaches, if one or more outside runways have an offset approach course of 2.5 to 3.0 the space between those outer runways and centreline may be reduced to 3000ft

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SIMULTANEOUS CLOSE PARALLEL PRECISION RUNWAY MONITOR ( PRM ) APPROCACHES .

This type of approaches are authorized for use at designated airports that have parallel runways spaced less than 4300 feet .

PRM procedures are the most efficient method of increasing approach capacity at airports which closely spaced, parallel runways . PRM increase airport capacity during low visibility by providing ATC the capability to monitor simultaneous close parallel independent approaches , and reduce delays and increase fuel savings.

there are also a special communication and ATC requirements for PRM approaches , require a final NTZ monitor controller for each runway, a separate tower controller for each runway.

Note : PRM approaches have a special approach charts.