B737-400
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Overcame Equipment Problem; Flight Crew Landed As Precaution; General Maintenance Action; General Flight Cancelled / Delayed
Aircraft
On visual approach; turning base to final inside 5 miles to touchdown on Runway XXL at ZZZ; the #1 Engine lost thrust and rolled back. It indicated 20 to 21% N1 for the remainder of the flight irrespective of the thrust lever position. I manually flew the airplane to the runway and landed. I requested my FO/PNF (First Officer/Pilot Not Flying) notify the Tower we had an engine failure just after passing below 500 ft. AGL. The Master Caution illuminated in flight; with ENG illuminated on the Master Caution annunciator. No other warning and no other caution lights illuminated. The engine ran at idle thrust and within acceptable parameters; but the thrust lever would not command additional thrust.Unknown why engine rolled back to idle in flight.Manually flew airplane single engine to a full stop landing on intended runway. Verified condition of engine my self and later commanding PNF to call out what he saw as failure. Notified ATC/Tower of engine failure.
Captain reported #1 engine rolled back and lost thrust on approach to landing.