Volga-Dnepr Airlines (VI, Ulyanovsk Vostochny) has denied its Leipzig/Halle-based MRO subsidiary, AMTES GmbH, is under criminal investigation for allegedly performing unauthorised maintenance procedures on the carrier's An-124-100s.

"AMTES and its management have not received any official notifications of a criminal case nor any enquiries or investigations from the law enforcement agencies of Ukraine or other countries of the Group's presence. There is no official information regarding the subject matter, scope or participants of the supposed investigation. All documents confirming the airworthiness of the An-124-100 aircraft were issued by the competent authorities of the Russian Federation and are fully compliant with international law," the cargo specialist said in a statement.

In mid-July, Ukrainian media reported that local police had asked its prosecution unit to open a criminal investigation into the alleged forgery of type certificates for An-124s operated by Volga-Dnepr Airlines.

According to the reports, the Ukrainian law enforcement believed that AMTES was performing unauthorised maintenance and repairs. On the basis of these procedures, the Russian air transport regulator (Rosaviatsia) allegedly extended the validity of type certificates of the said aircraft.

Antonov Design Bureau (Gostomel) argued it is the only company in the world with both the legal authorisation and know-how to perform such jobs.

According to the ch-aviation fleets module, Volga-Dnepr Airlines currently operates twelve An-124-100s and is the largest user of the type in the world. The airline and the manufacturer have been deadlocked since 2014 after the Crimean Crisis and the ensuing civil war in the Donbass with pro-Russian separatists, led to the severing of all relations between Russia and Ukraine.

The parties reportedly resumed talks about the extension of airworthiness certificates for the An-124 in November 2017 but no deal has materialised to date. Any prospective checks would have to be conducted in Russia as Russian-registered aircraft are currently barred from operating in Ukrainian airspace.