Is Radio Phraseology the same everywhere? “When ready” vs. “At Pilots Discretion”

Are you used to flying mostly within US airspace? Watch out for the meaning of ATC instructions outside of the US. They may not be the same.

EuroControl recently issued a safety briefing aimed at US pilots concerning the use of ‘AT PILOTS DISCRETION’ and ‘WHEN READY’ climb and descent clearances.

In many parts of the world, the phrases “When Ready” and “At Pilot’s Discretion” are used interchangeably in both voice and data link communications, indicating the associated instruction/clearance may be complied with or executed at any future time when the pilot is prepared to do so.

In US airspace only, and in the context of a climb/descend clearance, “At Pilot’s Discretion” also provides the flexibility for intermediate level offs after the climb or descent has been initiated by the pilot. However, a pilot may not return to any previously vacated levels. This option for an intermediate level off is ONLY PERMITTED IN US AIRSPACE. In all other airspace, the Pilot’s Discretion climb or descent is continuous.

EuroControl is reminding Aircraft operators that the option for an intermediate level off following an ‘AT PILOTS DISCRETION’ request to climb/descend applies only in US airspace.