Narrative:

I was the PF, well rested, with no known factors that would interfere with my flying. Mia departure gave us climb to 'one nine thousand.' the captain read back 'flight level one nine thousand.' at 10000 ft, miami told us to level at 10000 ft and we did. Controller then told us we had traffic 1000 ft above us. We both heard 'one nine thousand' and acknowledged it with a positive readback. Miami did not seem upset about it.

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Original NASA ASRS Text

Title: A NONSTANDARD USE OF TERMINOLOGY AND THE READBACK OF THE SAME LEADS TO CONFUSION AND A TFC CONFLICT BECAUSE OF THE RESULTING ALT OVERSHOOTS.

Narrative: I WAS THE PF, WELL RESTED, WITH NO KNOWN FACTORS THAT WOULD INTERFERE WITH MY FLYING. MIA DEP GAVE US CLB TO 'ONE NINE THOUSAND.' THE CAPT READ BACK 'FLT LEVEL ONE NINE THOUSAND.' AT 10000 FT, MIAMI TOLD US TO LEVEL AT 10000 FT AND WE DID. CTLR THEN TOLD US WE HAD TFC 1000 FT ABOVE US. WE BOTH HEARD 'ONE NINE THOUSAND' AND ACKNOWLEDGED IT WITH A POSITIVE READBACK. MIAMI DID NOT SEEM UPSET ABOUT IT.

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.