Narrative:

Slowly after departing iad with dca as destination we checked in with potomac departure, who told us to return back to iad. It appears that we have to use the 'code word' with them in order to continue and be vectored into dca. However, our understanding was that we have to use it with 'approach' and not 'departure.' while we thought that there would be 2 different sectors controling us from iad to dca, it turns out that apparently 'approach and 'departure' is the same 'office' controling traffic in and out of dca. As we were told by tower to contact 'departure' and not 'approach' we never used the code word on initial contact.

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Original NASA ASRS Text

Title: A CARJ200 CREW FAILED TO PROVIDE A CODE WORD TO DCA DEP CTL WHEN TRANSITING FROM ONE ARPT TO ANOTHER BOTH WITHIN THE DCA ADIZ. THE FLT WAS DIVERTED BACK TO IAD.

Narrative: SLOWLY AFTER DEPARTING IAD WITH DCA AS DEST WE CHKED IN WITH POTOMAC DEP, WHO TOLD US TO RETURN BACK TO IAD. IT APPEARS THAT WE HAVE TO USE THE 'CODE WORD' WITH THEM IN ORDER TO CONTINUE AND BE VECTORED INTO DCA. HOWEVER, OUR UNDERSTANDING WAS THAT WE HAVE TO USE IT WITH 'APCH' AND NOT 'DEP.' WHILE WE THOUGHT THAT THERE WOULD BE 2 DIFFERENT SECTORS CTLING US FROM IAD TO DCA, IT TURNS OUT THAT APPARENTLY 'APCH AND 'DEP' IS THE SAME 'OFFICE' CTLING TFC IN AND OUT OF DCA. AS WE WERE TOLD BY TWR TO CONTACT 'DEP' AND NOT 'APCH' WE NEVER USED THE CODE WORD ON INITIAL CONTACT.

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.