As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: HYDRAULIC YELLOW RESERVOIR LOW LEVEL. DIVERTED TO JFK AND DECLARED EMERGENCY. NORMAL LANDING AND BRAKING. NORMAL SMOOTH LANDING. REPLACED CHECK VALVE (AALA202107188405) ON YELLOW HYDRAULIC HIGH PRESSURE MANIFOLD IAW AMM 29-24-21. REPLACED HP MANIFOLD TEE FITTING (AALA202107197673) IAW AMM 29-13-14.