As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6330 - IAD-PIT - DURING TAXI, AIRCRAFT RETURNED TO GATE DUE TO RIGHT HYDRAULIC PUMP PRESSURE DROPPED TO ZERO. MAINTENANCE INSPECTED AND REMOVED AND REPLACED HYDRAULIC PUMP, OPS CHECK OK. AIRCRAFT WAS RELEASED AND RETURNED TO SERVICE. (M)