AIM 

3/21/24 

2.  CPDLC

−

DCL 

(a) 

No limitation to the number of clearances received. 

(b) 

Allows delivery of revised flight data, including revised departure clearances. 

(c) 

A response from the flight crew is required. 

(d) 

Requires a logon to the FAA National Single Data Authority 

−

 KUSA 

−

 utilizing the ATC FANS 

application. 

(e) 

To be eligible, operators must have received CPDLC/FANS authorization from the responsible civil 

aviation authority, and file appropriate equipment information in ICAO field 10a and in the ICAO field 18 DAT 

(Other Data Applications) of the flight plan. 

5

−

2

−

3.  IFR Clearances Off Uncontrolled Airports 

a. 

Pilots departing on an IFR flight plan should consult the Chart Supplement to determine the frequency or 

telephone number to use to contact clearance delivery. On initial contact, pilots should advise that the flight is 

IFR and state the departure and destination airports. 

b. 

Air traffic facilities providing clearance delivery services via telephone will have their telephone number 

published in the Chart Supplement of that airport’s entry. This same section may also contain a telephone number 

to use for cancellation of an IFR flight plan after landing. 

c. 

Except in Alaska, pilots of MEDEVAC flights may obtain a clearance by calling 1

−

877

−

543

−

4733. 

5

−

2

−

4.  Taxi Clearance 

Pilots on IFR flight plans should communicate with the control tower on the appropriate ground control or 

clearance delivery frequency prior to starting engines, to receive engine start time, taxi, and/or clearance 

information. 

5

−

2

−

5.  Line Up and Wait (LUAW) 

a. 

Line up and wait is an air traffic control (ATC) procedure designed to position an aircraft onto the runway 

for an imminent departure. The ATC instruction “LINE UP AND WAIT” is used to instruct a pilot to taxi onto 

the departure runway and line up and wait. 

EXAMPLE

−

 

Tower: “N234AR Runway 24L, line up and wait.” 

b. 

This ATC instruction is not an authorization to takeoff. In instances where the pilot has been instructed to 

line up and wait and has been advised of a reason/condition (wake turbulence, traffic on an intersecting runway, 

etc.) or the reason/condition is clearly visible (another aircraft that has landed on or is taking off on the same 

runway), and the reason/condition is satisfied, the pilot should expect an imminent takeoff clearance, unless 

advised of a delay. If you are uncertain about any ATC instruction or clearance, contact ATC immediately. 

c. 

If a takeoff clearance is not received within a reasonable amount of time after clearance to line up and wait, 

ATC should be contacted. 

EXAMPLE

−

 

Aircraft: Cessna 234AR holding in position Runway 24L. 

Aircraft: Cessna 234AR holding in position Runway 24L at Bravo. 

NOTE

−

 

FAA analysis of accidents and incidents involving aircraft holding in position indicate that two minutes or more elapsed 

between the time the instruction was issued to line up and wait and the resulting event (for example, land

−

over or 

go

−

around). Pilots should consider the length of time that they have been holding in position whenever they HAVE NOT been 

advised of any expected delay to determine when it is appropriate to query the controller. 

5

−

2

−

2 

Departure Procedures