What happened
On 30 June 2010, an ATR-72-500 (212A), registration EC-HJI, operated by Air Nostrum L.A.M., departed Madrid-Barajas Airport for Melilla. Shortly after takeoff, as the aircraft climbed through 9,000 feet, the crew noticed a slight mist appearing in both the cockpit and the passenger cabin.
At approximately 9,134 feet, a fire warning was triggered for the number 1 engine. The flight crew immediately initiated emergency procedures, discharging two extinguisher bottles to suppress the fire. Following the successful extinguishment, the crew requested priority handling to return to Madrid. The aircraft performed a single-engine approach and landed on runway 33L at 08:12:00. The aircraft then taxied to its parking position under its own power, escorted by airport firefighting services. There were no injuries among the 4 crew members or 64 passengers.
The investigation
The investigation focused on the mechanical failure of the Pratt & Whitney PW127F engine. Physical inspections of the aircraft revealed that while the airframe remained undamaged, the number 1 engine had sustained significant internal damage. Investigators found that the engine's power turbine was jammed, and there was evidence of fire outside the engine firewall, which had damaged various cables and lines.
Detailed disassembly of the engine revealed that several components, including the first and second-stage rotors of the power turbine and the stator, had been severely damaged by debris. Laboratory analysis of the broken blades confirmed that the failure originated from a fatigue fracture in a first-stage power turbine rotor blade, which contained micro-porosity from the manufacturing process.