B757 Undifferentiated or Other Model
Aircraft Equipment Problem Less Severe
General None Reported / Taken
Aircraft
On a stable normal ILS approach in VMC conditions; light winds; to Runway XXL we received a TE FLAP DISAGREE message and warning/caution after Captain selected Flaps 25.  The aircraft was configured for the ATC assigned 160 KTS to ZZZZZ Intersection (Flaps 20; gear down; autopilot ON).  Just prior to ZZZZZ; I called for Flaps 25 and began to slow the aircraft for final approach speed.  We received the message and after a brief scan of the instruments could see the flap lever was in the 25 detent; but the flap gauge indicated both remained in the Flaps 20 position.  Everything else appeared normal.  The Captain and I had a brief and succinct discussion about our situation and he said; 'Continue.'  He looked up the appropriate Flaps 20 landing speed and set it and I turned off the auto pilot and hand flew the remaining portion of the approach and landing.  The landing was uneventful otherwise. Once we cleared the runway we did not retract the flaps; called Operations and informed them we would be arriving with flaps extended and then called Maintenance.  Maintenance concurred that they wanted the flaps to remain as-is for inspection and said they would meet us at the gate for a de-brief.  We taxied to gate; parked; deplaned the passengers and waited for Maintenance. They arrived a few minutes later. At some point during the 5-10 minutes at the gate; the flaps recovered and extended to 25 to match the lever position.
B757 flight crew experienced a TE Flap Disagree on final approach when selecting Flaps 25. Flaps stayed at 20 and crew landed at adjusted speed without incident.