EMB ERJ 170/175 ER/LR
Flight Crew Air Transport Pilot (ATP)
Confusion; Communication Breakdown
ATC Issue All Types
General None Reported / Taken
Human Factors; Procedure; Chart Or Publication
This is regarding the new RNAV SIDs at IAH and the phraseology that they are using. I have not had any violations; but I believe that the wording they are using is non-standard and unsafe. There have been some memos regarding this; but I think ATC's phraseology is not quite apropos of Standard English. IAH Departure is using the verbiage; 'Climb via the XYZ SID; except maintain one six thousand feet' expecting us to climb via the SID and comply with all published altitude restrictions. Webster's dictionary defines except as: 'not including; other than; or with the exclusion or exception of.' Therefore; my interpretation of the statement they are issuing is to comply with the lateral and speed portions of the SID; and replace the altitude with the except altitude. Per the definition of 'except' followed by an altitude means 'with the exclusion of' such and such altitude.When I query them they educate me of their expectations of the statement and I now know what they expect.  I just believe that the statement could get crews who are unfamiliar with this into trouble; especially if they attempt to interpret the semantics according to Standard English usage. I believe that the verbiage should be 'climb via the XYZ SID; [maintain] XX thousand.'
An ERJ Captain reported his belief that IAH ATC's phraseology when clearing flights to specific altitudes using 'climb via' on the new RNAV SIDs is imprecise and may lead to flights failing to comply with intervening crossing restrictions.