What was found
ENGINE SURGE FL350 CRUISE M.80 MIN 4 BANGS NOT SHUTDOWN OPERATE NORMAL POST DESCENT ENG NR 1, 15-20 SEC. DURATION, ROLLED BACK TO 50%, WAS EXPERIENCING MOUNTAIN WAVE, DID NOT SPOOL BACK UP. THROTTLES WERE GOING BACK AND FORTH. ENGINE 2: 03 ENGINE 1: 03 OIL SERVICE ACCOMPLISHED AT DEN FOR FLT 0309 ON 04 MAR 14:44:49 ENGINE 3: ENGINE 4: APU: OPENED NR 1 ENGINE FAN AND REVERSER COWLS AND REMOVED APPLICABLE BORESCOPE PLUGS REF AMM 72-00-00-200-803-F00. LP 9092875 CREATED AGAINST AC 8803 TO CLEAR THIS ITEM FROM AC.