What was found
(CAN) DURING A SCHEDULED 1200 HOUR INSPECTION, A CRACK WAS FOUND ON A DOUBLER WHERE THE HORIZONTAL STAB MEETS THE VERTICAL STAB ON THE TAIL. MAINTENANCE GROUNDED THE AIRPLANE IMMEDIATELY. UPON FURTHER INVESTIGATION, IT WAS FOUND THAT THE BOLTS THAT HOLDS THE VERTICAL AND HORIZONTAL STAB TOGETHER WERE NOT TIGHT. BELIEVE THAT THIS WAS THE MAIN CAUSE FOR THE CRACK BECAUSE OF THE MOVEMENT/FLEXING OF THE TWO STRUCTURES. PLEASE SEE ATTACHED PHOTOS (TC NR 20091118013)