What was found
LAS - FLT 192 - AIR TURN BACK, CLIMBING THROUGH 18000 MSL, CAPTAINS WINDSHIELD BEGAN ARCING BADLY. THEN HEARD A DISTINCT POP AND IMMEDIATELY NOTICED A LARGE CRACK. REMOVED AND REPLACED LEFT WINDOW PER T/C R1B56001. REPLACED LEFT WINDOW CONTROLLER PER GPP. REFERENCE AWXA960113.