Ukrainian authorities have ordered detailed inspection of the fan discs on Ivchenko-Progress D-18T engines, following the destructive powerplant failure involving an Antonov An-124 last November.
The state aviation administration says preliminary investigation results show the fan disc was the “source” of the failure at Novosibirsk, which resulted in multiple system malfunctions on the freighter after take-off and a runway excursion as it returned to land.
Operators of An-124s as well as the sole An-225 are required to undertake one-time visual and eddy-current inspections of a specific area of the disc on D-18T series 3 engines.
These inspections must be conducted within six months or when engine time reaches 250h.
If defects to the disc are detected during the checks, says the administration, it must be replaced with a serviceable assembly. The results of the inspections should be sent to the design and manufacturing organisations.
No-one was injured during the incident involving the Vienna-bound Volga-Dnepr An-124 on 13 November but the crew had to cope with issues including reduced thrust control, brake failure, loss of electrical power, and loss of radio communication. The jet also sustained substantial wing and fuselage damage from the engine debris.