RuAviation

In early December 2025, the PD-8 turbofan engine successfully completed a mandatory fan blade-off certification test at the open-air test facility of UEC–Saturn in Rybinsk, Russia. The test verified fan case integrity following a simulated fan blade failure—one of the core safety requirements in commercial aircraft engine certification.

The objective of the test was to confirm that, in the event of a fan blade separation, all debris remains fully contained within the engine casing and does not pose a hazard to the aircraft structure.

During the test, the fan case performed its primary containment function under conditions replicating an in-flight emergency. Engineers used a low-energy explosive charge embedded in a pre-conditioned fan blade. After the engine reached the prescribed operating regime, an electrical signal initiated the charge, causing controlled blade separation.

“The blade separation occurs at a relatively high power setting, typically corresponding to takeoff thrust. This fully replicates real operational conditions. If the fan case remains intact after the event, the test is considered a pass,” said Alexey Veretennikov, Deputy Chief Designer for Testing at UEC–Saturn.

The PD-8 engine successfully passed the test. The fan case withstood the blade-off event, confirming the robustness of the design and completing a key element of the certification basis.
“This test brings the engine significantly closer to type certification and confirms its safety in critical operating scenarios,” added Olga Pervova, Head of the Process Engineering Bureau at UEC–Saturn’s test division.

Extensive preparatory work preceded the fan blade-off test. The test stand was equipped with specialized instrumentation, including a slip-ring assembly, a phasing system, and an air sampling system. The latter confirmed that, under real-world operating conditions, oil vapor emissions into the aircraft environmental control system would remain within permissible limits.

Earlier, the PD-8 engine successfully completed water ingestion tests, demonstrating reliable performance in heavy rainfall. UEC–Saturn specialists also evaluated the engine’s environmental noise footprint, crosswind operability, and thrust reverser functionality.

“All tests were conducted at thrust levels exceeding 17,600 lbf and confirmed the engine’s operational reliability,” UEC stated.