Narrative:

After departure ATC assigned altitude 10000 ft. 1 min later first officer set altitude select to 16000 ft and started climb. Not sure about that, asked first officer to verify again the altitude, no response from ATC and asked again, no response. Stopped the climb at 11000 ft and started descent back to 10000 ft. Then ATC responded, 'if I don't respond that means stay at 10000 ft, now climb and maintain 16000 ft.' the right thing to do was to question one more time the altitude.

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Original NASA ASRS Text

Title: AN EMJ CREW AFTER TKOF SNA NOT SURE OF ASSIGNED ALT ATTEMPT TO VERIFY WITH CTLR AND AFTER RESPONSE DELAY RECEIVED A NOT TOO FRIENDLY ANSWER.

Narrative: AFTER DEP ATC ASSIGNED ALT 10000 FT. 1 MIN LATER FO SET ALT SELECT TO 16000 FT AND STARTED CLB. NOT SURE ABOUT THAT, ASKED FO TO VERIFY AGAIN THE ALT, NO RESPONSE FROM ATC AND ASKED AGAIN, NO RESPONSE. STOPPED THE CLB AT 11000 FT AND STARTED DSCNT BACK TO 10000 FT. THEN ATC RESPONDED, 'IF I DON'T RESPOND THAT MEANS STAY AT 10000 FT, NOW CLB AND MAINTAIN 16000 FT.' THE RIGHT THING TO DO WAS TO QUESTION ONE MORE TIME THE ALT.

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.