ICAO is there to assist with SID/STAR phraseology implementation!

SIDs and STARs have proven to be effective means of ensuring that the flow of traffic to/from an airport is as efficient as possible and that potential conflicts are procedurally and safely managed. This is particularly so when combined with optimum airspace design in a PBN environment. Additionally, they provide a means of prescribing and representing the large amount of information associated with the lateral and vertical profiles an aircraft is required to fly. 

However, over time, some of the benefits of SIDS and STARS have been eroded as diverging and sometimes conflicting meanings were attached to elements of the phraseology. In particular, there were reports of significant variances in the application of level and speed restrictions, leading to misunderstandings between flight crews and controllers, a number of incidents and a very real safety risk.

To mitigate this risk and at the request of the aviation community, work was undertaken by the ICAO ATM Operations Panel (ATMOPSP), with extensive consultation throughout the development process. The agreed outcome led to new SID/STAR phraseologies that became applicable in 2016.


Why the need for new phraseologies?

The new 2016 phraseologies have been based upon a number of essential considerations, such as the need for controllers to communicate their intention to the flight crew clearly and succinctly and for the flight crew to fully understand the controller's intent. Clarity of clearances for speed and level restrictions on SIDs and STARs, including the waiving of published restrictions, have also been considered. Overall, the principle is that of explicit instructions, with no room for implied clearances. Care is also taken to ensure that the 2016 phraseology does not contradict existing phraseologies, that it is identical for SIDs and STARs and that it is suitable for global implementation.


Whilst the phraseologies have been applicable since 10 November 2016, by which date global implementation should have been completed, the actual picture is less ideal. Many States have indeed successfully completed their implementation, but others have yet to start. There are also instances of States choosing to delay or defer the implementation process, providing some valuable 'lessons learnt'. There is also at least one State that has, to-date, retained a variant of the procedures where the difference in procedures might either prove confusing or even be unknown to flight crews.

What needs to be done

In recognition of the safety imperative, the harmonized and timely deployment of the 2016 SID/STAR phraseologies are a high priority for ICAO with a parallel expectation from the wider aviation community.

Help is available!

For further information the ISSIT can be contacted at: [email protected]