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6/17/21 

AIM 

(b) 

Establish a line

of

sight to that landing 

point that is above and in front of the heavier 
preceding aircraft. 

(c) 

When possible, note the point of landing 

of the heavier preceding aircraft and adjust point of 
intended landing as necessary. 

EXAMPLE

 

A puff of smoke may appear at the 1,000

foot markings of 

the runway, showing that touchdown was that point; 
therefore, adjust point of intended landing to the 
1,500

foot markings. 

(d) 

Maintain the line

of

sight to the point of 

intended landing above and ahead of the heavier 
preceding aircraft; maintain it to touchdown. 

(e) 

Land beyond the point of landing of the 

preceding heavier aircraft. Ensure you have adequate 
runway remaining, if conducting a touch

and

go 

landing, or adequate stopping distance available for 
a full stop landing. 

f. 

During visual approaches pilots may ask ATC 

for updates on separation and groundspeed with 
respect to heavier preceding aircraft, especially when 
there is any question of safe separation from wake 
turbulence. 

g. 

Pilots should notify ATC when a wake event is 

encountered. Be as descriptive as possible (i.e., bank 
angle, altitude deviations, intensity and duration of 
event, etc.) when reporting the event. ATC will record 
the event through their reporting system. You are also 
encouraged to use the Aviation Safety Reporting 
System (ASRS) to report wake events. 

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9.  Air Traffic Wake Turbulence 

Separations 

a. 

Because of the possible effects of wake 

turbulence, controllers are required to apply no less 
than minimum required separation to all aircraft 
operating behind a Super or Heavy, and to Small 
aircraft operating behind a B757, when aircraft are 
IFR; VFR and receiving Class B, Class C, or TRSA 
airspace services; or VFR and being radar sequenced. 

1. 

Separation is applied to aircraft operating 

directly behind a super or heavy at the same altitude 
or less than 1,000 feet below, and to small aircraft 
operating directly behind a B757 at the same altitude 
or less than 500 feet below: 

(a)  Heavy

 behind 

super 

 6 miles. 

(b)  Large

 behind 

super 

 7 miles. 

(c)  Small

 behind 

super 

 8 miles. 

(d)  Heavy

 behind 

heavy 

4 miles. 

(e)  Small/large

 behind 

heavy 

 5 miles. 

(f)  Small

 behind 

B757 

 4 miles. 

2. 

Also, separation, measured at the time the 

preceding aircraft is over the landing threshold, is 
provided to small aircraft: 

(a)  Small

 landing behind 

heavy 

 6  miles. 

(b)  Small

 landing behind 

large, non

B757 

  4 miles. 

REFERENCE

 

Pilot/Controller Glossary Term

 Aircraft Classes. 

b. 

Additionally, appropriate time or distance 

intervals are provided to departing aircraft when the 
departure will be from the same threshold, a parallel 
runway separated by less than 2,500 feet with less 
than 500 feet threshold stagger, or on a crossing 
runway and projected flight paths will cross: 

1. 

Three minutes or the appropriate radar 

separation when takeoff will be behind a super 
aircraft; 

2. 

Two minutes or the appropriate radar 

separation when takeoff will be behind a heavy 
aircraft. 

3. 

Two minutes or the appropriate radar 

separation when a small aircraft will takeoff behind 
a B757. 

NOTE

 

Controllers may not reduce or waive these intervals. 

c. 

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 

 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 

Wake Turbulence 

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