Narrative:

Air carrier X inbound to ATC on the long side transition to downwind was instructed to descend to 10000 ft mistakenly instead of 12000 ft, which I meant to issue. The aircraft entered the ATC departure controller's airspace without coordination. I noticed the aircraft descending below 11000 ft and instructed the aircraft to climb and maintain 11000 ft. There are several factors that I feel contributed to this error. We were very busy. I was controling 9 or 10 arriving aircraft. I was concentrating on the short side arrs since they were coming into my airspace at minimum in trail with speeds up. I had to vector them off the arrival for spacing, since our finals were already full. Descent to 10000 ft is normal practice for this short side traffic. Thinking of the necessity to get these aircraft down to 10000 ft, I must have misspoke that altitude when descending a long side aircraft. Supplemental information from acn 306048: I was working the D handoff. The center was feeding us at minimum interval and we were getting no relief from flow control (tmu). The sector was overloaded. I coordinated directly with the center to give us a gap. They did but an aircraft that went missed approach filled that gap. Tmc was coordinating with me telling me they had stopped arrs at logan, when the controller issued a short side altitude to a long side airplane. I missed the clearance and readback. The aircraft descended into departure's airspace.

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Original NASA ASRS Text

Title: 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.

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.