Ukrainian authorities have ordered Antonov An-124 operators to inspect engines on the type after an uncontained powerplant failure.

An-124s are fitted with Ivchenko-Progress D-18T engines, as is the sole example of the An-225.

The Ukrainian state aviation administration says an investigation into the “serious incident”, which occurred to an An-124, traced the failure to destruction of the second-stage disk in the intermediate pressure compressor.

It has not specified the incident which prompted the directive, but has instructed operators to carry out a one-time inspection of the disks in all D-18T series 3 powerplants.

The directive, which takes effect from 25 March, is an interim measure, says the administration, and further corrective measures are set to be developed.

Operators must conduct the eddy-current inspection of disk dovetails within six months, it adds, and send the results to the manufacturer, Motor-Sich, as well as Ivchenko-Progress. If cracks are detected, the engine must be removed for corrective action.