What was found
(CAN) DURING INSPECTION AFT GPS ANTENNA SEALENT WAS NOTICED TO BE CRACKED AND THE ANTENNA WAS LOOSE. UPON REMOVING THE ANTENNA, 3.5 INCH CRACKED WAS FOUND ON THE TAILCONE SKIN. THE CRACK DID NOT ORIGINATE FROM ANY OF THE MANUFACTURED RIVET OR SCREW HOLES. IT COULD NOT BE DETERMINED IF THE ANTENNA HAD BEEN PULLED ON AS THERE WAS NO DAMAGE TO THE ANTENNA OR BENDING OF THE TAILCONE SKIN. PICTURES HAVE BEEN FORWARDED TO TRANSPORT MAINTENANCE AND MANUFACTURER. THE TAILCONE HAS BEEN SENT TO THE MANUFACTURER FOR INSPECTION AND REPAIR.