Narrative:

Initially leaving bwi we were cleared to 4000. When turned over to departure, if we were given a further climb clearance we did not acknowledge it. I do not remember hearing a climb clearance. We did not reset the altitude alerter to a higher altitude. About 20-25 mi west of bwi we saw a target on our TCASII indicating 300 ft below us and about 3 mi, 12 O'clock. After asking departure about traffic, he confirmed it, and asked if we had begun our climb out of 4000 for 17000 ft. We said we hadn't received a climb clearance. He said to start climb which we did immediately. The other aircraft did not become a collision threat and we saw it visually as we climbed. The only clue that something was wrong was it seemed we had been at 4000 ft longer than normal, but I thought there was perhaps crossing traffic above us.

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Original NASA ASRS Text

Title: ACR MLG MISSED AMENDED CLRNC ALT ASSIGNMENT UNTIL TCASII TA CAUSED THEM TO QUESTION DEP CTLR.

Narrative: INITIALLY LEAVING BWI WE WERE CLRED TO 4000. WHEN TURNED OVER TO DEP, IF WE WERE GIVEN A FURTHER CLB CLRNC WE DID NOT ACKNOWLEDGE IT. I DO NOT REMEMBER HEARING A CLB CLRNC. WE DID NOT RESET THE ALT ALERTER TO A HIGHER ALT. ABOUT 20-25 MI W OF BWI WE SAW A TARGET ON OUR TCASII INDICATING 300 FT BELOW US AND ABOUT 3 MI, 12 O'CLOCK. AFTER ASKING DEP ABOUT TFC, HE CONFIRMED IT, AND ASKED IF WE HAD BEGUN OUR CLB OUT OF 4000 FOR 17000 FT. WE SAID WE HADN'T RECEIVED A CLB CLRNC. HE SAID TO START CLB WHICH WE DID IMMEDIATELY. THE OTHER ACFT DID NOT BECOME A COLLISION THREAT AND WE SAW IT VISUALLY AS WE CLBED. THE ONLY CLUE THAT SOMETHING WAS WRONG WAS IT SEEMED WE HAD BEEN AT 4000 FT LONGER THAN NORMAL, BUT I THOUGHT THERE WAS PERHAPS XING TFC ABOVE US.

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.