Two years ago, the Catalyst engine did not exist. Now it is entering the next stretch of testing and certification before it begins flying later this year.
Built to power the brand-new Cessna Denali single engine turboprop passenger plane, the Catalyst has been developed at a breakneck pace at GE Aviation Czech in Prague, the company’s headquarters for turboprop engines.
The Prague team is also exploiting the collaboration started in 2016 with the Czech Technical University (CTU). The University will be developing and designing the new engine’s preventive maintenance monitoring model with the support of GE Aviation’s expertise and know-how. CTU will soon benefit from its two new test facilities currently under construction.
The new test cells will be situated on the grounds of the Hradce Králové Airport, a historically significant location for Czech aviation, about 125 kilometers west of Prague. Built in 1927 by the Czechoslovakian National Air Force, the airport was occupied by Germany during the Second World War and expanded to serve as a training center. Modernized in the 1950s, Hradce Králové can accommodate any type of aircraft but is currently only used for private aviation. The airport turns out to be precisely what the Catalyst team needed: a safe, controlled environment where the engine can be spooled up, measured, tweaked, and tested.
“The new test cells are under construction inside the hangar structure that originally housed aircraft such as the MiG-21,” explains Radek Novotny, project leader for the test cells. “Both in the front and in the back of the room, an excellent system will be able to reduce within legal limits any noises generated by the engine, the primary compressor, and the propeller, even up to noises similar to those coming from an airplane during takeoff.”
“Both test cells can accommodate the engine equipped with the propeller,” says Clarice Carmone, supply chain program leader for the Catalyst at GE Aviation Czech. This is an essential step in the lead-up to the engine’s first official flight and final certification.
The testing can sometimes take on the look of a surgical operation. At the Avio Aero Sangone Experimental Center, where a team has been busy prepping the Catalyst engine before it is shipped to Prague, a tangle of more than 500 ultra-thin transmission cables, each only 0.8mm in diameter, connect the engine to a series of external and internal sensors that collect and measure valuable performance data under different operating conditions. This enables the engineers to evaluate the Catalyst’s overall duration, resistance, and vibrations.
“During these kinds of tests, vibrations occur, especially toward the external structures of the aircraft that house both engine and propeller,” Engine Test Leader and Instrumentation Design Engineer Piergiorgio Belloni explains. “Transient acceleration or deceleration maneuvers are also carried out with decidedly significant levels of engine power.” Put another way: they push the Catalyst to its limits.
“Since 2016, we have been supporting early Catalyst testing, including but not limited to the responsibility of the design of the whole engine’s instrumentation for the vibrations test,” says Belloni.
Jiri Machula is the Instrumentation Labs Manager at GE Aviation Czech. He and his team have worked side by side with Belloni and the Italian team responsible for the Catalyst’s instrumentation. “In Turin, they designed the complete engine instrumentation, which we then assembled here, sharing process and methods,” Machula says. “This has allowed us to significantly increase the capabilities and expertise of both our teams, and then to further transmit this knowledge to other GE Aviation laboratories in Europe.”
The Italian team has built much of the instrumentation operations thanks to the 3D modeling at the heart of the design. Utilizing a “digital twin”—that is, the virtual reproduction of the engine and all of its instrumentation—the team has been able to verify every configuration, in real time, in a virtual environment, thereby reducing any errors or risk of interference that could occur while operating the physical engine.
“Every single part of the instrumentation has been produced in a digital 3D environment,” says Belloni. “It was the first time that we in Avio Aero used this method on a whole engine. When I think of all the times I’ve worked with the engine on the screen, what amazes me most is its final correspondence with reality. It looks exactly how I imagined it!”