Narrative:

While holding over armel VOR at 12000', we were instructed to 'in the turn, proceed direct armel, direct washington, descend and maintain 8000',' by dulles approach. We were then handed off to washington approach. Prior to crossing armel and leveling at 8000', we contacted washington approach, who then told us to 'turn right heading 160, vectors for the ILS 36 at washington, descend and maintain 4000.' passing through 6400', washington approach asked us to 'say altitude,' to which we responded 6400'. We were then instructed to 'level off at 6000.' supplemental information from acn 132490: I cleared the aircraft direct aml direct dca descend and maintain 8000'. The pilot asked for dca RVR's, it was given to me as 4000'. I told the pilot dca RVR 4000, the handoff was completed and I switched the aircraft. Dca called later and asked why he was descending to 4000', that iad approach had descended the aircraft. I replied I did not descend the aircraft and advised dca to stop the aircraft at 6000'. The supervisor was notified and I was relieved from the position. After reviewing the tapes, it was determined that the aircraft was cleared to 8000'. The pilot had also read back 8000'.

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Original NASA ASRS Text

Title: ACR MLG BEING HANDED OFF FROM IAD TRACON TO DCA TRACON DESCENDS BELOW PROPER ALT.

Narrative: WHILE HOLDING OVER ARMEL VOR AT 12000', WE WERE INSTRUCTED TO 'IN THE TURN, PROCEED DIRECT ARMEL, DIRECT WASHINGTON, DSND AND MAINTAIN 8000',' BY DULLES APCH. WE WERE THEN HANDED OFF TO WASHINGTON APCH. PRIOR TO XING ARMEL AND LEVELING AT 8000', WE CONTACTED WASHINGTON APCH, WHO THEN TOLD US TO 'TURN RIGHT HDG 160, VECTORS FOR THE ILS 36 AT WASHINGTON, DSND AND MAINTAIN 4000.' PASSING THROUGH 6400', WASHINGTON APCH ASKED US TO 'SAY ALT,' TO WHICH WE RESPONDED 6400'. WE WERE THEN INSTRUCTED TO 'LEVEL OFF AT 6000.' SUPPLEMENTAL INFO FROM ACN 132490: I CLRED THE ACFT DIRECT AML DIRECT DCA DSND AND MAINTAIN 8000'. THE PLT ASKED FOR DCA RVR'S, IT WAS GIVEN TO ME AS 4000'. I TOLD THE PLT DCA RVR 4000, THE HDOF WAS COMPLETED AND I SWITCHED THE ACFT. DCA CALLED LATER AND ASKED WHY HE WAS DSNDING TO 4000', THAT IAD APCH HAD DSNDED THE ACFT. I REPLIED I DID NOT DSND THE ACFT AND ADVISED DCA TO STOP THE ACFT AT 6000'. THE SUPVR WAS NOTIFIED AND I WAS RELIEVED FROM THE POS. AFTER REVIEWING THE TAPES, IT WAS DETERMINED THAT THE ACFT WAS CLRED TO 8000'. THE PLT HAD ALSO READ BACK 8000'.

Data retrieved from NASA's ASRS site as of August 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.