Narrative:

Crossing jaybo intersection at FL240 ZDC informed us we were supposed to be at 15000 ft. Our last assigned altitude was FL240. He told us to maintain FL240 and gave us a frequency change. Immediately after checking in, we received a TCASII RA. We took evasive action, descending and turning away from the contact. ZDC then questioned us as to our altitude. I informed him we were at FL230, having descended in response to a TCASII RA. With the traffic in sight, we climbed back to FL240 as requested. After some communication confusion with vectors we rejoined the dpnt 3 arrival and proceeded to phl.

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Original NASA ASRS Text

Title: AN ACR MLG CREW FAILED TO MAKE AN ALT XING, THEN HAD A TCASII ALT FROM THEIR NEWLY RE-ASSIGNED ALT.

Narrative: XING JAYBO INTXN AT FL240 ZDC INFORMED US WE WERE SUPPOSED TO BE AT 15000 FT. OUR LAST ASSIGNED ALT WAS FL240. HE TOLD US TO MAINTAIN FL240 AND GAVE US A FREQ CHANGE. IMMEDIATELY AFTER CHKING IN, WE RECEIVED A TCASII RA. WE TOOK EVASIVE ACTION, DSNDING AND TURNING AWAY FROM THE CONTACT. ZDC THEN QUESTIONED US AS TO OUR ALT. I INFORMED HIM WE WERE AT FL230, HAVING DSNDED IN RESPONSE TO A TCASII RA. WITH THE TFC IN SIGHT, WE CLBED BACK TO FL240 AS REQUESTED. AFTER SOME COM CONFUSION WITH VECTORS WE REJOINED THE DPNT 3 ARR AND PROCEEDED TO PHL.

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.