What was found
LT PACK OFF, PACK FAILED, UNABLE TO MAINTAIN CABIN PRESS WITH RT PACK, OUTFLOW VALVE CLOSED, CL 1200 FPM. RAN BOTH ENGINES, PERFORMED CHECK IAW AMM, NO FAULTS NOTED. FOUND DUCT BOOT LOOSE IN RT PACK BAY RECONNECTED. REPLACED LT ENGINE PRSOV PRECAUTIONARY. (K)