Narrative:

I was working the west radar position at asheville approach control. The traffic involved was an aircraft swbnd, IFR at 9000' from tri approach control; and a military bmb beyond our radar coverage to the west, coordinated to enter the IR075 route, and restr to 10000' to provide sep from an aircraft which was crossing the IR075 route. When the military bmb came on my frequency, he inquired if he was still restr to 10000'. Intending to confirm the restriction to stay at or above 10000' and not descend into the route altitudes, I transmitted something to the effect: 'affirmative, maintain 10000', traffic is crossing the route at 9000'.' the normal IR075 entry altitudes are 12000' west of sot VOR, descend to 11000' at point C, descend to 10000' at point cc, and descend to 7700' at point east. The military bmb was still west of sot VOR when I made the transmission, and the aircraft descended immediately to 10000' from ZTL airspace, through tys approach airspace, into asheville approach airspace. I realized as I observed what took place that the pilot followed my instruction exactly and descended to maintain 10000', instead of following the published route altitudes. I should have issued the altitude as a restriction to the route altitudes: 'fly the published route altitudes, not below 10000'.'

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Original NASA ASRS Text

Title: CTLR DESCENDED A MIL BMB INTO ANOTHER FAC'S AIRSPACE WITHOUT COORD. OPERATIONAL DEVIATION.

Narrative: I WAS WORKING THE W RADAR POS AT ASHEVILLE APCH CTL. THE TFC INVOLVED WAS AN ACFT SWBND, IFR AT 9000' FROM TRI APCH CTL; AND A MIL BMB BEYOND OUR RADAR COVERAGE TO THE W, COORDINATED TO ENTER THE IR075 ROUTE, AND RESTR TO 10000' TO PROVIDE SEP FROM AN ACFT WHICH WAS XING THE IR075 ROUTE. WHEN THE MIL BMB CAME ON MY FREQ, HE INQUIRED IF HE WAS STILL RESTR TO 10000'. INTENDING TO CONFIRM THE RESTRICTION TO STAY AT OR ABOVE 10000' AND NOT DSND INTO THE ROUTE ALTS, I XMITTED SOMETHING TO THE EFFECT: 'AFFIRMATIVE, MAINTAIN 10000', TFC IS XING THE ROUTE AT 9000'.' THE NORMAL IR075 ENTRY ALTS ARE 12000' W OF SOT VOR, DSND TO 11000' AT POINT C, DSND TO 10000' AT POINT CC, AND DSND TO 7700' AT POINT E. THE MIL BMB WAS STILL W OF SOT VOR WHEN I MADE THE XMISSION, AND THE ACFT DSNDED IMMEDIATELY TO 10000' FROM ZTL AIRSPACE, THROUGH TYS APCH AIRSPACE, INTO ASHEVILLE APCH AIRSPACE. I REALIZED AS I OBSERVED WHAT TOOK PLACE THAT THE PLT FOLLOWED MY INSTRUCTION EXACTLY AND DSNDED TO MAINTAIN 10000', INSTEAD OF FOLLOWING THE PUBLISHED ROUTE ALTS. I SHOULD HAVE ISSUED THE ALT AS A RESTRICTION TO THE ROUTE ALTS: 'FLY THE PUBLISHED ROUTE ALTS, NOT BELOW 10000'.'

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.