Russian engine specialist Aviadvigatel has started testing a gas generator of the PD-14 turbofan for United Aircraft's MS-21 twin-jet.
The firm says it is keeping up with schedule in developing the PD-14 and has built a special test bench to validate the core demonstrator, fitted with 1,200 sensors.
During the first test run, verification of aeromechanical characteristics and operating modes involved more than 800 parameters, with their number to increase to 2,000 gradually.
In a deviation from the original concept, Aviadvigatel has chosen a two-stage high-pressure turbine and eight-stage high pressure compressor scheme for the hot core section.
Speaking at a scientific conference in Moscow, chief designer Alexander Inozemtsev said: "Initially, we envisaged a one-stage and six-stage configuration.
"Following a two-year research programme, we had to abandon that architecture and develop a completely new gas generator to achieve higher fuel efficiency and lower emission."
Inozemtsev details a co-operation scheme for PD-14 production. Perm Motors will produce hot core modules and carry out engine integration, while NPO Saturn is to supply low-pressure modules - apart from turbine blades, which will be fabricated by the Ufa-based firm UMPO.
Alongside design bureau Motor, UMPO will be responsible for the development of the low-pressure turbine. Moscow aviation materials institute VIAM is developing a technology to coat turbine blades with alloys to combat corrosion.
"Perm Motors is to accommodate a coating line, for which special equipment has been purchased," says Inozemtsev. "To carry out materials certification, it has also installed six machines with further four to be added next year."
Ground testing of the PD-14 will involve an open-air facility near Saturn's production plant in Rybinsk, which was built for testing the PowerJet SaM146 engine.
Aircraft manufacturer Irkut, which steers the development of the MS-21, wants its engine nacelles to be made of composite materials. Inozemtsev says Aviadvigatel is working on setting up a joint venture to this effect with VIAM and a Western specialist.