What happened
On March 6, 2002, an MD-82, registration I-DAVL, was operating flight AZA 1600 from Bari to Rome Fiumicino with 37 passengers and 6 crew members on board. While descending through flight level 140, the aircraft entered a cloud formation and encountered severe turbulence, experiencing vertical accelerations of up to 3.182 g.
The violent motion caused several simultaneous issues: a flight attendant was thrown from their seat, striking their head against the ceiling and sustaining various contusions; the rigid enclosure for the aft emergency slide ruptured, causing the slide to deploy and partially inflate within the tail cone; and a smoke warning was triggered in the rear right lavatory. Shortly after the turbulence, the crew identified high oil temperature and low oil pressure/quantity in the right engine. Following emergency procedures, the crew shut down and isolated the right engine and requested priority landing.
The investigation
The ANSV investigation examined the aircraft' and the flight's technical and human factors. Investigators analyzed the flight data, engine components, and the tail cone assembly. The investigation focused on the aircraft's speed during the turbulence encounter, the maintenance history of the right engine, and the inspection of the slide container. The probe also reviewed meteorological charts and the crew's performance regarding weather assessment and communication.
Findings
- The primary active cause was the excessive airspeed maintained when entering the severe turbulence zone; the aircraft was traveling at 313 knots, whereas the optimal speed for such conditions should have been below 285 knots.
- A failure in the right engine's lubrication system occurred due to a broken recovery pump shaft, which was linked to a lack of proper oversight by a maintenance technician during a previous engine assembly.
- The deployment of the tail cone slide was caused by an ineffective inspection of the slide's housing in the 24 hours preceding the flight.
- The crew failed to properly analyze meteorological charts that indicated severe turbulence was present in the flight path.
- There was a breakdown in crew communication, as the flight attendant did not fully inform the commander of the severity of the colleague's injuries, and the commander did not notify the cabin crew regarding the engine shutdown.