What was found
AFTER SELECTING FLAPS 1, GOT EICAS MESSAGE FLAPS PRIMARY FOLLOWED BY FLAP DRIVE. RT INBD L/E FLAP NOT IN COMMANDED POSITION. PERFORMED QRH PROCEDURE AND LANDED UNEVENTFULLY. R & R L/E NR 4 FLAP UNIT IAW AMM 27-81-03-2, REV 72, JUL 15/2011. OPS AND LEAK CHECKED SATIS. PDU NR4, 4R.