Clearances for Departing and Arriving Aircraft

Feature Desk, Aviation Gurukul, GOLN

3 years ago

Communication Failure Guidance for Controllers

Clearances for Departing and Arriving Aircraft

Background

This article is courtesy of ICAO, which published in June 2016 Amendment 7-A to PANS-ATM, applicable as of 10 November 2016.

A very important part of this amendment is the changed harmonized phraseology for issuing standard clearances to arriving and departing aircraft, including clearances to aircraft on a SID or STAR. The purpose of this change to the phraseology is to:

provide core phraseology that positively reinforces that the lateral, vertical, and speed requirements embedded in a SID or STAR will continue to apply unless explicitly canceled or amended by the controller;
provide supplementary phraseology that enables any level and/or speed restrictions as local circumstances, practice, or procedures permit;
harmonize through appropriate phraseology how aircraft must be cleared where variations to the lateral profile are required, such as where waypoints along the procedure are bypassed.

Standard Clearances for Departing Aircraft

Standard clearances for departing aircraft shall contain the following items:

aircraft identification;
clearance limit, normally destination aerodrome;
designator of the assigned SID, if applicable;
cleared level;
allocated SSR code;
any other necessary instructions or information not contained in the SID description, e.g. instructions relating to change of frequency.

Note: The use of a SID designator without a cleared level does not authorize the aircraft to climb on the SID vertical profile.

Standard Clearances for Arriving Aircraft

Standard clearances for arriving aircraft shall contain the following items:

aircraft identification;
designator of the assigned STAR if applicable;
runway-in-use, except when part of the STAR description;
cleared level; and
any other necessary instructions or information not contained in the STAR description, e.g. change of communications.

Note: The use of a STAR designator without a cleared level does not authorize the aircraft to descend on the STAR vertical profile.

Clearances to Aircraft on SIDs and STARs

Standard Instrument Departures (SIDs) and Standard Instrument Arrivals (STARs) provide a safe and efficient way of prescribing a large amount of information through procedure design.

Both depict the lateral profile of an instrument departure or arrival route and the level and speed restrictions along with it.

SID/STAR phraseology allows ATC and aircrew to communicate and understand detailed clearance information that would otherwise require long and potentially complex transmissions.

Over time, these benefits have been eroded through the development of non-harmonized practices and different meanings being attached to certain elements of SID/STAR phraseology. Consequently, there may be a mismatch between ATC and aircrew expectations when SID/STAR phraseology is used, and what certain terms may mean.

This presents a safety risk that requires the adoption of harmonized SID/STAR phraseology.

In June 2016 ICAO published Amendment 7-A to PANS-ATM, applicable as of 10 November 2016, which includes harmonized phraseologies for issuing standard clearances to arriving and departing aircraft, including clearances to aircraft on a SID or STAR. The phraseology can be consulted in “Further Reading” below.

The period over which the changes should be introduced has been notified by ICAO as 12 months commencing 10 November 2016, i.e. implementation date will vary from state to state depending on the NAA.

The transition period will likely affect pilots making international IFR flights. Also, controllers from ATC Units in States which have not begun using the new procedures themselves should be aware that pilots from other States which have done so are likely to use them.

SID/STAR Phraseology

Core phraseology:

CLIMB VIA SID TO (level)
DESCEND VIA STAR TO (level)

These require the aircraft to:

Climb/descend to the cleared level by published level restrictions;
Follow the lateral profile of the procedure; and
Comply with published speed restrictions or ATC-issued speed control instructions as applicable.

Phraseology for removal of speed or level restrictions:

CLIMB VIA SID TO (level), CANCEL SPEED RESTRICTION(S)
DESCEND VIA STAR TO (level), CANCEL LEVEL RESTRICTION(S) AT (point(s))

This mean that:

The lateral profile of the procedure continues to apply and
Speed or level restrictions that have not been referred to will continue to apply.

Phraseology for variations to the lateral profile of the SID/STAR:

PROCEED DIRECT (waypoint), or
Vectoring of aircraft (using appropriate phraseology)

This means that speed and level restrictions associated with the bypassed waypoints are canceled.

Phraseology to return to SID/STAR:

REJOIN SID/STAR

This means that speed and level restrictions associated with the waypoint where the rejoin occurs, as well as those associated with all subsequent waypoints must be complied with.

Read the complete text of the changed provisions and phraseology of Amendment No.7-A to the PANS-ATM (Doc 4444) applicable on 10 November 2016.