B777 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Distraction; Time Pressure
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Unstabilized Approach
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Overcame Equipment Problem
ATC Equipment / Nav Facility / Buildings; Aircraft
ZZZZ; weather via ATIS was VFR. RWY XXL closed for maintenance/construction. Glideslope fluctuations occurring RWY XXR. Crew discussed the cautions of flying into ZZZZ. Terrain; Approach speeds; missed approach procedures for single and two engine and variable wind due to terrain. All crew members had been to ZZZZ many times before. Cleared for ILS XXR starting at 2000 feet 2 miles from FAF. Aircraft was configured gear down; flaps 25; speed 160 knots and autopilot on. I noted an amber AUTOPILOT on EICAS to FO (First Officer) who was flying the approach. When I looked at the Primary Flight Display; the green GS on FMA had an amber bar drawn across it. Flight Director had turned amber with full down deflection on it. I instructed the FO to maintain altitude. The [Relief Pilot] confirmed and repeated it to FO. Autopilot was disconnected. FO asked for FD (Flight Director) to be turned off. Flaps 30 selected. Approach continued with visual using VASI bars. Before Landing Checklist completed. Aircraft was in normal landing profile at 500 feet. Landed in the TDZE (touchdown zone). The First Officers; (all former Captains) and I with 100 plus years experience had not seen this event before. This might be a good training scenario.
B777 Captain reported a glideslope warning on final approach and continued using the VASI.