How to protect yourself from a level bust or worse due to incorrect altitude acquisition during a SID/STAR

ICAO Doc 4444 PANS-ATM (15th Edition) has recently been modified with Amendments 7a and 7b. Among the many changes contained in this document is a solution for the phraseological ambiguities with SID and STAR altitude and speed restrictions. With regards to altitudes, what are the operator’s expectations when given an altitude or flight level above the level published in the SID? For instance, should a pilot continue with the SID altitude profile and climb to the cleared altitude after the SID (as per ICAO procedure), or commence with the climb immediately?

The published phraseologies in Amendment 7a address these issues. According to this amendment, if an issued clearance to an altitude or flight level is higher than any restriction in a SID, the pilot must comply with all restrictions and commence the climb to the cleared altitude or flight level only after the SID. Specific instructions must be given by the controller when canceling the vertical restrictions associated with a SID. These new procedures have been in effect since November 10, 2017. However, as of this writing no country has adopted the new procedures. Canada did have plans to be the first country to adopt the new procedures, but has recently postponed the implementation to the latter half of 2017, possibly to October.

When operators consider a country’s AIP rules, they may find themselves in a conundrum. In some instances, a country’s AIP only makes vague references to Doc 4444 in Gen Section 1.7: Differences from ICAO Standards, Recommended Practices and Procedures.  Some countries are either reluctant or choosing to delay the implementation of the new phraseology procedures. Without interim procedures in place, the operator may have to resort to the ICAO rules prior to the Amendment 7a changes. Not knowing whether a country even adopts the procedure just cited leaves a crew, at best, uneasy as to their next move.

There are two phrases that may be used in a read back of a vertical clearance while flying a SID or STAR that will ensure a safe execution of the clearance. When one reads back the altitude assignment, they should include the words, “UNDERSTAND COMPLY WITH RESTRICTIONS, climb to FL120.” Countries that have not adopted the previous ICAO rules governing climbs and descents while on a SID or STAR should then provide information as to what is to be expected. That country may use “UNRESTRICTED CLIMB” to inform the pilot that the clearance they just gave cancelled the vertical restriction of the SID.

As we know, many countries deviate from ICAO standards, and therefore one should always review Gen Section 1.7: Differences from ICAO Standards, Recommended Practices and Procedures in the respective countries’ AIP to verify these differences. I personally like the procedure adopted by the UK for this issue. In the UK, if a controller sees that the pilot is not climbing in accordance with the clearance given, they will reissue the clearance reiterating the cancelation of the restrictions accompanied by the phrase “CLIMB NOW.” Now that makes sense.

Read full review of the SID/STAR phraseology changes put forward.

Shawn Scott is the co-owner and co-founder of Scott International Procedures, LLC. The company provides International Procedures training to professional pilots within the business aviation community.