Alitalia Flight 404Wednesday November 14, 1990
The aircraft continued to descend after intercepting the glide slope and hit high ground 6 miles from the airport. False indication of VHF NAV on unit No.1 in the aircraft. Possible misread altimeter by the pilot-in-command. Lack of GPWS warning in the cockpit. Crew was not aware of the possibility of incorrect indications in the NAV equipment in use. Non-compliance with basic procedural instructions during the approach. ATC did not observe the leaving of the cleared altitude of 4,000 ft.