Narrative:

The flight was cleared the rbv 1 arrival (eno.rbv 1) to ewr. Prior to reaching davys intersection, ZDC cleared the flight to proceed direct to holey intersection and maintain 11000 ft. The flight was then handed off to new york approach with the first officer reporting 11000 ft on initial contact. New york approach then cleared the flight to proceed direct to the owbie intersection. Shortly thereafter, TCASII displayed a TA, and the crew received vocal warning of 'traffic, traffic.' TCASII display indicated that the conflicting aircraft would pass behind us and 11000 ft was maintained. Immediately thereafter, new york approach queried us as to our altitude. The first officer responded level at 11000 ft. New york approach then ordered us to 'descend immediately to 8000 ft.' the autoplt and autothrottles were immediately disengaged, spoilers deployed, and we immediately began descent to 8000 ft at maximum rate of descent. New york approach then queried us as to why we were maintaining 11000 ft, and the first officer responded that it was the last assigned altitude. New york approach then requested that we change transponder code to a newly issued code, which was complied with. The flight continued to ewr without further event.

Related reports:

Google
 

Original NASA ASRS Text

Title: AFTER FREQ CHANGE FROM ZDC TO N90 APCH CTL, RPTING LEVEL AT 11000 FT, AN MD82 FLC RECEIVES A TCASII TA. FOLLOWING THE TCASII ADVISORY APCH CTL QUERIES FLC'S ALT AND IS ISSUED AN IMMEDIATE DSCNT TO 8000 FT.

Narrative: THE FLT WAS CLRED THE RBV 1 ARR (ENO.RBV 1) TO EWR. PRIOR TO REACHING DAVYS INTXN, ZDC CLRED THE FLT TO PROCEED DIRECT TO HOLEY INTXN AND MAINTAIN 11000 FT. THE FLT WAS THEN HANDED OFF TO NEW YORK APCH WITH THE FO RPTING 11000 FT ON INITIAL CONTACT. NEW YORK APCH THEN CLRED THE FLT TO PROCEED DIRECT TO THE OWBIE INTXN. SHORTLY THEREAFTER, TCASII DISPLAYED A TA, AND THE CREW RECEIVED VOCAL WARNING OF 'TFC, TFC.' TCASII DISPLAY INDICATED THAT THE CONFLICTING ACFT WOULD PASS BEHIND US AND 11000 FT WAS MAINTAINED. IMMEDIATELY THEREAFTER, NEW YORK APCH QUERIED US AS TO OUR ALT. THE FO RESPONDED LEVEL AT 11000 FT. NEW YORK APCH THEN ORDERED US TO 'DSND IMMEDIATELY TO 8000 FT.' THE AUTOPLT AND AUTOTHROTTLES WERE IMMEDIATELY DISENGAGED, SPOILERS DEPLOYED, AND WE IMMEDIATELY BEGAN DSCNT TO 8000 FT AT MAX RATE OF DSCNT. NEW YORK APCH THEN QUERIED US AS TO WHY WE WERE MAINTAINING 11000 FT, AND THE FO RESPONDED THAT IT WAS THE LAST ASSIGNED ALT. NEW YORK APCH THEN REQUESTED THAT WE CHANGE XPONDER CODE TO A NEWLY ISSUED CODE, WHICH WAS COMPLIED WITH. THE FLT CONTINUED TO EWR WITHOUT FURTHER EVENT.

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.