Pilot/Controller Glossary

4/3/14

PCG A−1

A

AAI−

(See ARRIVAL AIRCRAFT INTERVAL.)

AAR−

(See AIRPORT ARRIVAL RATE.)

ABBREVIATED IFR FLIGHT PLANS− An

authorization by ATC requiring pilots to submit only

that information needed for the purpose of ATC. It

includes only a small portion of the usual IFR flight

plan information. In certain instances, this may be

only aircraft identification, location, and pilot

request. Other information may be requested if

needed by ATC for separation/control purposes. It is

frequently used by aircraft which are airborne and

desire an instrument approach or by aircraft which are

on the ground and desire a climb to VFR-on-top.

(See VFR-ON-TOP.)
(Refer to AIM.)

ABEAM

−  An aircraft is “abeam” a fix, point, or

object when that fix, point, or object is approximately

90 degrees to the right or left of the aircraft track.

Abeam indicates a general position rather than a

precise point.

ABORT

−  To terminate a preplanned aircraft

maneuver; e.g., an aborted takeoff.
ACC [ICAO]−

(See ICAO term AREA CONTROL CENTER.)

ACCELERATE-STOP DISTANCE AVAILABLE−

The runway plus stopway length declared available

and suitable for the acceleration and deceleration of

an airplane aborting a takeoff.
ACCELERATE-STOP DISTANCE AVAILABLE

[ICAO]− The length of the take-off run available plus

the length of the stopway if provided.
ACDO−

(See AIR CARRIER DISTRICT OFFICE.)

ACKNOWLEDGE

−  Let me know that you have

received and understood this message.
ACL−

(See AIRCRAFT LIST.)

ACLS−

(See AUTOMATIC CARRIER LANDING

SYSTEM.)

ACLT−

(See ACTUAL CALCULATED LANDING TIME.)

ACROBATIC FLIGHT− An intentional maneuver

involving an abrupt change in an aircraft’s attitude, an

abnormal attitude, or abnormal acceleration not

necessary for normal flight.

(See ICAO term ACROBATIC FLIGHT.)
(Refer to 14 CFR Part 91.)

ACROBATIC FLIGHT [ICAO]− Maneuvers inten-

tionally performed by an aircraft involving an abrupt

change in its attitude, an abnormal attitude, or an

abnormal variation in speed.
ACTIVE RUNWAY−

(See RUNWAY IN USE/ACTIVE RUNWAY/DUTY

RUNWAY.)

ACTUAL CALCULATED LANDING TIME−

ACLT is a flight’s frozen calculated landing time. An

actual time determined at freeze calculated landing

time (FCLT) or meter list display interval (MLDI) for

the adapted vertex for each arrival aircraft based upon

runway configuration, airport acceptance rate, airport

arrival delay period, and other metered arrival

aircraft. This time is either the vertex time of arrival

(VTA) of the aircraft or the tentative calculated

landing time (TCLT)/ACLT of the previous aircraft

plus the arrival aircraft interval (AAI), whichever is

later. This time will not be updated in response to the

aircraft’s progress.
ACTUAL NAVIGATION PERFORMANCE

(ANP)−

(See REQUIRED NAVIGATION

PERFORMANCE.)

ADDITIONAL SERVICES− Advisory information

provided by ATC which includes but is not limited to

the following:

a.

Traffic advisories.

b.

Vectors, when requested by the pilot, to assist

aircraft receiving traffic advisories to avoid observed

traffic.

c.

Altitude deviation information of 300 feet or

more from an assigned altitude as observed on a

verified (reading correctly) automatic altitude

readout (Mode C).

d.

Advisories that traffic is no longer a factor.