Incident Overview

Description
Alitalia flight 4128, a DC-9-30, crashed into the sea while on approach to Palermo-Punta Raisi Airport, Italy, killing 108 occupants; 21 survived the accident. The Alitalia DC-9-32, named “Isola di Stromboli”, impacted the sea and crashed while on approach to Palermo-Punta Raisi Airport, Italy. The aircraft operated Alitalia flight 4128, an extra service for the Christmas season from Rome’s Fiumicino Airport to Palermo on the isle of Sicily. The flight was cleared for a night-time VOR/DME approach to runway 21. The approach procedure dictated to establish on the 217 degree radial inbound of Raisi VOR/DME (identification PRS) at “Guffy” point, located 16.5 NM north-east of the VOR at 4000 feet on local QNH, then descend in order to cross the 6 DME fix at 1500 feet, the 4 DME fix at 900 feet, the 3 DME fix at 700 feet. The latter fix is also the Missed Approach Point, where, should the runway not be in sight, the crew should initiate a go-around, turning right on a 332 degree heading, climb to 3000 feet and wait for ATC instructions. The final part of the approach, about two miles, is to be flown visually with the crew having to turn left to line up for runway 21, which had a magnetic heading of 206 degrees. The aircraft stopped descent at about 150 feet above the sea after passing the 3 DME fix, as if the pilot was trying to locate the final approach area, thinking to be very close to the runway. This feeling was enhanced by the light geometry around the airport. For about nine seconds the aircraft flew almost level with the sea at 150 knots, then the wind helped to loose the final feet and the right wing impacted water. Twenty-one survivors were saved by nearby fishing boats. At that time, Palermo Airport was equipped with a primary radar Plessey ACR430, with an operative range of no more than 15 miles, usable on the North and West quadrants only due to high terrain to the East and South, and with no MTI (Moving Target Indicator) able to suppress the fixed returns, with the consequence that the inner three miles are almost blind spots to the controller. Having no secondary radar capability, the equipment is not able to give transponder answers to the controller (no identification codes and no altitude reporting), any aircraft appearing just as small unlabelled target on the screen. Reported weather at time of crash was: wind from South, variable betw een South and South-West, up to more than 30 knots, visibility more than 10 kilometers, scattered cumulus clouds to the West with distant showers. Piloting the aircraft was the first officer (seven years as F/E, just three months as pilot, with 173 hours on the DC-9). The captain was a senior pilot, with great experience on the Caravelles, but just 418 hours on the DC-9.
Primary Cause
Pilot error and inadequate radar system redundancy.Pilot error and inadequate radar system redundancy.Share on: