As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHX-TUS - FLT 606 - AIR TURN BACK, SHORTLY AFTER GEAR RETRACTION, 'B' SYSTEM HYDRAULIC QUANTITY DROPPED TO 1 GALLON AND HELD. SHUT OFF 'B' SYSTEM. FOUND NR 1 SPOILER PRESSURE RELIEF CAP O-RING BLOWN OUT. REPLACED O-RING, SERVICED HYDRAULICS. FUNCTION CHECKED GOOD, OPERATES NORMAL. (M)