Narrative:

Aircraft was on an opd routing. ZDC controller called and informed me that due to weather deviations; this aircraft was cleared to FL220 and not issued the descend via part of their clearance. The pilot contacted my sector and stated that they had the descend via clearance which put them in conflict with another aircraft. The opd procedures at this position have been wrought with many unclear situations. The pilots aren't sure of what to do when they have been issued a clearance (notably speed or altitude assignments) that differs from the published procedure. Controllers may not be sure of what clearances to issue in these cases and the correct way to issue these clearances. The problems are probably worse than they should be because of two facilities issuing clearances and using varying phraseology. To solve part of these problems; clearance phraseology should be in the same.

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Original NASA ASRS Text

Title: ZTL Controller voiced concern regarding the varied phraseology used within ATC when clearing 'descend via' clearances.

Narrative: Aircraft was on an OPD routing. ZDC Controller called and informed me that due to weather deviations; this aircraft was cleared to FL220 and not issued the descend via part of their clearance. The pilot contacted my sector and stated that they had the descend via clearance which put them in conflict with another aircraft. The OPD procedures at this position have been wrought with many unclear situations. The pilots aren't sure of what to do when they have been issued a clearance (notably speed or altitude assignments) that differs from the published procedure. Controllers may not be sure of what clearances to issue in these cases and the correct way to issue these clearances. The problems are probably worse than they should be because of two facilities issuing clearances and using varying phraseology. To solve part of these problems; clearance phraseology should be in the same.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.