An air carrier pilot reported GPS jamming in LLLL airspace resulted in numerous terrain warnings; FMS; GPS; and EFB failures.
Synopsis
An air carrier pilot reported GPS jamming in LLLL airspace resulted in numerous terrain warnings; FMS; GPS; and EFB failures.
Narrative
Near south of Gaza area aircraft experienced jamming; possible spoofing and various single and dual GPS loss… with eventuality (only) the right GPS coming back… POS page…other faults ATC FAULT; status page TERR system. Both IPADs (and sometimes GPSs) showed aircraft position was over 100 miles away and not moving; POS page. Over Egypt at FL320 aircraft experienced a momentary terrain warning and pull-up command. During configuration phase On ILS final 14L CGN aircraft experienced a solid terrain warning…aircraft was stabilized; in CAVOK/VMC; on/on on ILS GS/flight director; visual with runway and VASI…altitude verified. Warning was discussed and crew confirmed aircraft was stabilized and in position (as mentioned above); and with the known previous terrain; GPS issues; decided to continue the approach. Terrain override was selected to eliminate the terrain warning. Aircraft landed without incident.Some factors were; previous terrain warning at Fl320; terrain status message; GPS and other associated faults; carried forward; difficultly communicating with terrain warning announcing; aircraft fully stabilized and confidence by crew aircraft was in its correct position.
Second reporter narrative
Initially cruising at FL320 and near Israeli Airspace; we experienced GPS jamming which led to EICAS messages; including ATC fault; L GPS; TERR POS; and Erroneous EGPWS Terrain warning. We also received a TERR SYS status message which remained on for the duration of flight. We also experienced spoofing and our GPS position was unreliable at times. All EICAS messages went away while enroute; but on final approach at approximately 2500 ft MSL; we received another erroneous terrain warning on EGPWS and an TERR POS EICAS message. We verified our position on the ILS with LOC/GS captured and on glideslope; in VMC; runway in sight; on the VASI path; and completely stable. We discussed the situation and agreed to continue the approach and disabled the nuisance warnings with the TERR OVRD switch. The question would be whether we should have performed a CFIT (controlled flight into terrain); but the system was already known to be malfunctioning and we had experienced the same erroneous errors at FL320. Furthermore; I believe the malfunction would have continued if we had not disabled it using TERR OVRD. There was no need to go-around and I made the command decision to continue given safety of the flight was in no way compromised.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.