PPRuNe Forums - View Single Post - El Al flight nearly crashed in Jerusalem hills
Old 4th Feb 2009, 04:44
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Shore Guy
 
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I'll pose the same questions as before (see previous post)

As to EGPWS warnings, if not a direct GPS feed to unit, and appropriate software/terrain database installed, close to the airport, protections are disabled to virtual GPWS status due to lack of confidence in position (even if FMS has a GPS input). All EGPWS manufacturers, Boeing, Airbus, and regulatory authorities STRONGLY recommend direct GPS input to EGPWS.
Future software will take advantage of Geometric Altitude (GPS derived) to further enhance (in case of incorrectly set altimeters) protections.
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