What was found
AT FL280 50 MINUTES AFTER TAKEOFF RECEIVED TE FLAP ASYM WITH ASSOCIATED TRAILING EDGE ANNUNCIATOR. COMPLIED WITH QRH. DECLARED EMERGENCY WITH BILLINGS APPROACH AND MADE SLATS EXTENDED, FLAPS 0 LANDING. 09MAY21 09:32 BIL R ATA CHANGED:: NEW ATA ::2750 OLD ATA ::0 CHANGED BY ::5222131 CHANGED ON ::2021-05-09 09:32:59.276 FACT 09MAY21 09:41 BIL U PERFORMED A BITE TEST OF ALL FSEU. NO EXISTING FAULTS FOUND. PERFORMED AN OPERATOINAL TEST OF THE FLAPS AND SLATS, AND CHECKED RESOLVERS AT FLAPS 20 DEGREES. NO DISAGREE BETWEEN FSEUS. NO FAULT INDICATION ON EICAS. ALL WORK PERFORMED IN ACCORDANCE WITH B757 AMM 27-51-00-5. OKAY FOR SERVICE.