Narrative:

Our pre departure clearance was the tralr RNAV 1 departure, with a cleared altitude of 7000 ft. As we switched over from las tower to las departure, we gave our altitude leaving and our cleared altitude of 7000 ft. Departure replied, 'maintain 7000 ft.' just prior to roppr (SID, at or below 7000 ft) they cleared us to 8000 ft. We crossed roppr at 7000 ft and then climbed to 8000 ft, and then we were cleared direct to tralr. On a more recent flight to ord, as before we were given 8000 ft just prior to roppr, but given an unrestr climb to FL190 after roppr. It appears departure control, restating 'maintain 7000 ft' was his acknowledgement to our call, and was not meant to cancel the SID altitude restrs. Supplemental information from acn 605794: we were leveling at 7000 ft when the captain mistakenly accepted a climb clearance meant for another aircraft. The controller corrected the captain and told us we needed to maintain 8000 ft. We started a climb to 8000 ft approximately 2 mi prior to roppr. The tralr 1 required that we cross roppr 'at or below 7500 ft.' we crossed roppr above the altitude required on the SID.

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Original NASA ASRS Text

Title: 2 DIFFERENT PERCEPTIONS OF WHAT MAY HAVE BEEN AN ALT EXCURSION PRIOR TO XING THE ROPPR FIX ON THE TRALR RNAV 1 DEP FROM LAS VEGAS, NV.

Narrative: OUR PDC WAS THE TRALR RNAV 1 DEP, WITH A CLRED ALT OF 7000 FT. AS WE SWITCHED OVER FROM LAS TWR TO LAS DEP, WE GAVE OUR ALT LEAVING AND OUR CLRED ALT OF 7000 FT. DEP REPLIED, 'MAINTAIN 7000 FT.' JUST PRIOR TO ROPPR (SID, AT OR BELOW 7000 FT) THEY CLRED US TO 8000 FT. WE CROSSED ROPPR AT 7000 FT AND THEN CLBED TO 8000 FT, AND THEN WE WERE CLRED DIRECT TO TRALR. ON A MORE RECENT FLT TO ORD, AS BEFORE WE WERE GIVEN 8000 FT JUST PRIOR TO ROPPR, BUT GIVEN AN UNRESTR CLB TO FL190 AFTER ROPPR. IT APPEARS DEP CTL, RESTATING 'MAINTAIN 7000 FT' WAS HIS ACKNOWLEDGEMENT TO OUR CALL, AND WAS NOT MEANT TO CANCEL THE SID ALT RESTRS. SUPPLEMENTAL INFO FROM ACN 605794: WE WERE LEVELING AT 7000 FT WHEN THE CAPT MISTAKENLY ACCEPTED A CLB CLRNC MEANT FOR ANOTHER ACFT. THE CTLR CORRECTED THE CAPT AND TOLD US WE NEEDED TO MAINTAIN 8000 FT. WE STARTED A CLB TO 8000 FT APPROX 2 MI PRIOR TO ROPPR. THE TRALR 1 REQUIRED THAT WE CROSS ROPPR 'AT OR BELOW 7500 FT.' WE CROSSED ROPPR ABOVE THE ALT REQUIRED ON THE SID.

Data retrieved from NASA's ASRS site as of July 2007 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.