What was found
CLT - FLT 1664 - AFTER T/O FROM CLT TO MDT, A/C EXPERIENCED A DUAL PACK FAILURE. LT PACK TRIPPED, THEN THE RT. FLT RETURNED TO CLT AND LANDED INCIDENT. MAINTENANCE R&R THE RT ENGINE HIGH STAGE REGULATOR PER MM 36-11-86 FOR THE RT PACK. OPS CHECK GOOD. LT PACK, THE 35 DEGREE SENSOR SLOW TO RESPOND. REPLACED 35 DEGREE SENSOR FOR LT PACK. RESPONDS NORMAL. FURTHER TROUBLESHOOTING REVEALED A LT PACK VALVE NOT FULLY OPENING. REPLACED LT PACK VALVE. OPS CHECK GOOD. ALSO, FOUND A FAILED LT RAM AIR TEMP CONTROLLER, RAM AIR TEMP SENSOR AND A SLOW OPERATING RAM AIR ACTUATOR. REPLACED LT RAM AIR TEMP CONTROLLER, SENSOR AND ACTUATOR PER MM. ALL OPERATIONALLY CHECK GOOD. ALSO, REPLACED WORN ROLLERS AND TRACKS F