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4/20/23 

AIM 

1. 

From an intersection on the same runway (same or opposite direction) behind a departing 

large

 aircraft 

(except B757), or 

2. 

In the opposite direction on the same runway behind a large aircraft (except B757) takeoff or low/missed 

approach. 

NOTE

 

This 3

minute interval may be waived upon specific pilot request. 

d. 

A 3

minute interval will be provided when a small aircraft will takeoff: 

1. 

From an intersection on the same runway (same or opposite direction) behind a departing B757, or 

2. 

In the opposite direction on the same runway behind a B757 takeoff or low/missed approach. 

NOTE

 

This 3

minute interval may not be waived. 

e. 

A 4

minute interval will be provided for all aircraft taking off behind a super aircraft, and a 3

minute 

interval will be provided for all aircraft taking off behind a heavy aircraft when the operations are as described 

in subparagraphs c1 and c2 above, and are conducted on either the same runway or parallel runways separated 

by less than 2,500 feet. Controllers may not reduce or waive this interval. 

f. 

Pilots may request additional separation (i.e., 2 minutes instead of 4 or 5 miles) for wake turbulence 

avoidance. This request should be made as soon as practical on ground control and at least before taxiing onto 

the runway. 

NOTE

 

14 CFR Section 91.3(a) states: “The pilot

in

command of an aircraft is directly responsible for and is the final authority 

as to the operation of that aircraft.” 

g. 

Controllers may anticipate separation and need not withhold a takeoff clearance for an aircraft departing 

behind a 

large, heavy, 

or

 super

 aircraft if there is reasonable assurance the required separation will exist when 

the departing aircraft starts takeoff roll. 

NOTE

 

With the advent of new wake turbulence separation methodologies known as Wake Turbulence Recategorization, some of 

the requirements listed above may vary at facilities authorized to operate in accordance with Wake Turbulence 

Recategorization directives. 

REFERENCE

 

FAA Order JO 7110.659 Wake Turbulence Recategorization. 

FAA Order JO 7110.123 Wake Turbulence Recategorization 

 Phase II. 

FAA Order JO 7110.126, Consolidated Wake Turbulence. 

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10.  Development and New Capabilities 

a. 

The suite of available wake turbulence tools, rules, and procedures is expanding, with the development of 

new methodologies. Based on extensive analysis of wake vortex behavior, new procedures and separation 

standards are being developed and implemented in the US and throughout the world.  Wake research involves 

the wake generating aircraft as well as the wake toleration of the trailing aircraft. 

b. 

The FAA and ICAO are leading initiatives, in terminal environments, to implement next

generation wake 

turbulence procedures and separation standards. The FAA has undertaken an effort to recategorize the existing 

fleet of aircraft and modify associated wake turbulence separation minima. This initiative is termed Wake 

Turbulence Recategorization (RECAT), and changes the current weight

based classes (Super, Heavy, B757, 

Large, Small+, and Small) to a wake

based categorical system that utilizes the aircraft matrices of weight, 

wingspan, and approach speed. RECAT is currently in use at a limited number of airports in the National Airspace 

System. 

Wake Turbulence 

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