TRUCK TURNED ONTO RWY WHEN LCL CTLR AT NKT WAS DEPARTING TFC.

Narrative

THE ACTIVE RWY WAS RWY 32. GND CTL TAXIED SEVERAL ACFT OUT FOR DEP. MIL X (HARRIER) WAS DEPARTING VFR TO A SMALL OUTLET FIELD 15 MI SW NKT; WIND WAS CALM. I ASKED THE PLT IF HE COULD ACCEPT A RWY 23L DEP; WIND CALM. HE SAID AFFIRMATIVE. I ADVISED MIL X TO TAXI UP TO AND HOLD SHORT RWY 23L. I REQUESTED RWY 5R FROM GND CTLR AND HE ADVISED ME IT WAS CLR AND MINE. A STUDENT CTLR WAS WORKING GND CTL WITH A QUALIFIED CTLR. I ADVISED MIL X TAXI INTO POS AND HOLD RWY 23L. AS I WAS GIVING THE CLRNC FOR TKOF; I SCANNED THE RWY; ISSUED WIND; AND CLRED HIM FOR TKOF. I REACHED OVER TO ANNOTATE THE COUNT AND LOOKED UP TO SCAN THE RWY AND I OBSERVED A TRUCK PROCEEDING UP THE INACTIVE PORTION OF RWY 5R. I ASSUMED GND CTLR GAVE HIM THE CLRNC; BUT FORGOT TO INFORM ME. I WAS ABOUT TO ADVISE THE PLT WHEN I OBSERVED THE TRUCK TURN 'ONTO' THE RWY. I IMMEDIATELY CANCELED THE TKOF CLRNC AND HOLD. THE PLT ACKNOWLEDGED. I ASKED GND CTLR WHAT WAS GOING ON; AND THE STUDENT SAID HE HAD FORGOTTEN HE HAD GIVEN THE TRUCK (WHICH IS OUR RECOVERY PERSONNEL) A 'BLANKET' ON THAT RWY. A 'BLANKET' IS A CLRNC TO A VEHICLE APPROVING HIS MOVEMENT ON 'THAT' RWY FOR AS LONG AS THEY NEED IT. THIS PARTICULAR TRUCK WAS CHKING THE ARRESTING CABLES FOR THAT RWY. MY CONCERN IS THAT THIS 'BLANKET' CLRNC HAPPENS ALMOST EVERY DAY AND MOST LIKELY THE RECOVERY PERSONNEL HAD BEEN OUT THERE FOR 15+ MINS. I HAVE ADVISED THE TWR PERSONNEL IF THEY INSIST ON USING THIS PRACTICE; THEY AT LEAST NEED TO REQUEST AN ENTRY AND EXIT CALL FROM THE DRIVER.