Alitalia Flight 404: A Disagreement in the Cockpit caused Deadly Consequences
Alitalia Flight 404 captain and his first officer are at odds over the data they receive, as they make their landing approach to Zurich Airport. It is a disagreement that ends in the crash of Alitalia 404, on November 14, 1990.
Alitalia Flight 404 was an international flight scheduled to fly from Linate Airport in Milan, Italy, to Zurich Airport in Zurich, Switzerland, which crashed on November 14, 1990.
The Douglas DC-9-32, operated by Alitalia, crashed into the woodlands of Weiach as it approached Zurich Airport killing all 46 people on board.
During the approach to runway 14 of Zurich International Airport, the pilot’s instrument landing system display gave incorrect values due to a faulty receiver.
It falsely indicated that the aircraft was about 1,000 feet higher than it actually was. The ILS receiver of the co-pilot was working correctly and displayed the dangerously low approach.
Without thoroughly examining which value was correct, the pilot decided to ignore the second device, aborting a go-around maneuver initiated by the co-pilot. Shortly afterward, at 19:11 CET, the plane struck Stadlerberg Mountain at 1,660 feet, killing all 40 passengers and six crew.
The aircraft’s first impact was with trees on the right side of the aircraft, causing several essential parts on the right side of the aircraft, such as the right-wing flaps and the outer right wing, to detach. As a result, the aircraft produced an asymmetric lift force and began to roll to the right, finally slamming into the mountain in a nearly inverted position.
A Swiss investigation concluded that the crash was caused by a short circuit, which led to the failure of the aircraft’s NAV receiver.
The malfunction went unnoticed by the crew, who likely believed they were on the correct flight path until the crash. Swiss authorities also blamed inadequate Crew Resource Management experienced when the pilot vetoed the co-pilot’s attempted go-around, along with the absence of lighting on Stadlerberg Mountain and the Drum Pointer Altimeter of the aircraft.
The final report by the Federal Aircraft Accidents Inquiry Board requested several major changes and made further recommendations