Date & Time:
Dec 23, 1978 at 0039 LT
Type of aircraft:
Douglas DC-9
Operator:
Registration:
I-DIKQ
Flight Phase:
Landing (descent or approach)
Flight Type:
Charter/Taxi (Non Scheduled Revenue Flight)
Survivors:
Yes
Site:
Lake, Sea, Ocean, River
Schedule:
Rome - Palermo
MSN:
47227
YOM:
1968
Flight number:
AZ4128
Country:
Italy
Region:
Europe
Crew on board:
5
Crew fatalities:
5
Pax on board:
124
Pax fatalities:
103
Other fatalities:
0
Total fatalities:
108
Captain / Total hours on type:
418
Copilot / Total hours on type:
173
Circumstances:
Following an uneventful flight from Rome-Fiumicino, the crew started the descent to Palermo-Punta Raisi Airport by night and good visibility (up to 10 km). Following a 'normal' VOR/DME approach, the crew continued the descent down to 150 feet over the sea when, at 3 km from the shore, the pilot-in-command (the copilot in this case) initiated a slight turn to the left to join runway 21. At a speed of 150 knots, the left wing tip struck the water surface and the aircraft crashed into the sea. All five crew members and 103 passengers were killed while 21 others were rescued by fishermen.
Probable cause:
It was determined that the last portion of the approach was completed in visual mode with a relative low rate of descent. The approach was started prematurely and the crew descended below the minimum descent altitude after several points of the approach checklist have been missed. It is possible that the crew have been misled by the malfunction of one or more altimeters due to an erroneous indication of the warning flag. Douglas and Collins informed Alitalia in 1975 already about the possible malfunction of those altimeters and their respective warning flag systems.
