ACR X UNAUTH UNCOORD PENETRATION OF DEP CTL AIRSPACE. OPDEV.

Narrative

ACR X INBOUND TO ATC ON THE LONG SIDE TRANSITION TO DOWNWIND WAS INSTRUCTED TO DSND TO 10000 FT MISTAKENLY INSTEAD OF 12000 FT; WHICH I MEANT TO ISSUE. THE ACFT ENTERED THE ATC DEP CTLR'S AIRSPACE WITHOUT COORD. I NOTICED THE ACFT DSNDING BELOW 11000 FT AND INSTRUCTED THE ACFT TO CLB AND MAINTAIN 11000 FT. THERE ARE SEVERAL FACTORS THAT I FEEL CONTRIBUTED TO THIS ERROR. WE WERE VERY BUSY. I WAS CTLING 9 OR 10 ARRIVING ACFT. I WAS CONCENTRATING ON THE SHORT SIDE ARRS SINCE THEY WERE COMING INTO MY AIRSPACE AT MINIMUM IN TRAIL WITH SPDS UP. I HAD TO VECTOR THEM OFF THE ARR FOR SPACING; SINCE OUR FINALS WERE ALREADY FULL. DSCNT TO 10000 FT IS NORMAL PRACTICE FOR THIS SHORT SIDE TFC. THINKING OF THE NECESSITY TO GET THESE ACFT DOWN TO 10000 FT; I MUST HAVE MISSPOKE THAT ALT WHEN DSNDING A LONG SIDE ACFT. SUPPLEMENTAL INFO FROM ACN 306048: I WAS WORKING THE D HDOF. THE CTR WAS FEEDING US AT MINIMUM INTERVAL AND WE WERE GETTING NO RELIEF FROM FLOW CTL (TMU). THE SECTOR WAS OVERLOADED. I COORDINATED DIRECTLY WITH THE CTR TO GIVE US A GAP. THEY DID BUT AN ACFT THAT WENT MISSED APCH FILLED THAT GAP. TMC WAS COORDINATING WITH ME TELLING ME THEY HAD STOPPED ARRS AT LOGAN; WHEN THE CTLR ISSUED A SHORT SIDE ALT TO A LONG SIDE AIRPLANE. I MISSED THE CLRNC AND READBACK. THE ACFT DSNDED INTO DEP'S AIRSPACE.