What was found
FLT NR 448 TPA-BOS, WHEN EXTENDING FLAPS FOR LANDING SLAT FAIL EICAS MESSAGE APPEARED, LANDED BOS WITH FLAP HANDLE AT POS.2. FDE DETAIL SLAT FAIL SURFACE JAMMED. FAULT CODE 27811021ACE. FIM REF 27-81-00-810-802-A, RELEASED PDU, BRAKE RELEASE NORMAL SMOOTH OPERATION NOTED. REPLACED S/F ACE NR 1 PER AMM 27-53-02 CK GOOD.