GE’s Catalyst turboprop promises to be a game-changer


General Electric (GE) has announced the new name for its Catalyst turboprop, previously known as the Advanced Turboprop (ATP).

Vice-president and general manager of GE’s Business Brad Mottier argues the new name is very appropriate, as the engine will indeed “be a catalyst for change, a catalyst for competition to work and a catalyst for new platforms”.

Now, why is the Catalyst expected to be such a game-changer? As Paul Corkery, GE Aviation Turboprop director general explained, “very little technology infusions” have been made in the turboprop market since decades. GE injected mature technologies from its commercial and military portfolio into its new turboprop engine to boost its performance. Among its innovative technologies are its advanced compressor design with IGV (Inlet Guided Vanes) on its first two stages, pushing the pressure ratio to 16:1 and reducing the lapse rate due to altitude; and cooled turbine blades which allow higher burning temperature, thus contributing to fuel consumption reduction by 15% to 20%, according to GE.

Another remarkable characteristic is that the engine is built with additive manufacturing. In addition to diminishing the engine’s development cycle’s length by 30% in comparison to current cycles, this brings down the total number of its components from 855 in classic assembly, to 12. This diminishes component-failure risk and, according to GE, the engine’s average time between overhaul (TBO) is expected to reach 4000 hours. It also reduces the engine’s weight by 5%, thus contributing to a 1% improvement in specific fuel consumption.

The Catalyst is also equipped with the first Full Authority Digital Engine and Propeller Control (FADEPC) on the turboprop market. By replacing the usual hydromechanical commands, this system will reduce commands to one single throttle, which greatly simplifies the pilot’s task, as he can stop constantly focusing on the gauges inside the cockpit and concentrate on other tasks, providing a more “jet-like” experience.

The ATP’s rebranding occurs a little over two years after Textron Aviation selected GE’s turboprop engine to power its Cessna Denali in November 2015, surprisingly breaking from its long association with P&WC and its monopolistic PT6.

GE Aviation has come up with a long-term strategy which aims to develop the first successful challenger to P&WC’s popular turboprop engine. This process began in 2008 when GE acquired Czech manufacturer Walter, maker of the M601, a Soviet-era alternative to the PT6. According to Brad Mottier, this was the first step toward acquiring the ability to understand turboprop customers’ needs – which are very different from that of airliners’ needs.

For the time being the Catalyst is still in its test phase. The first engine to test (FETT) has completed 33 minutes of running since December 2017 in GE Czech’s test bench and is now installed in a test-rig in the Czech Technical University’s Centre of Aerospace and Space Technology (CVUT) in Prague.

In cooperation with Czech researchers from the University, it will now be used to “develop a database of predictive maintenance requirements for individual turboprop engines” Michael Valàsek, said CVUT Dean. The CVUT will now be playing a major role in the Catalyst’s tests programme, as it will add a propeller and a core test cell to its Dyno test cell capabilities, in order to enhance test options and performance. In addition, CVUT has acquired a King Air 350 to serve as a flying test bench for the FETT.

A second Catalyst prototype, nicknamed “Engine 5”, is in its final assembly phase in Prague. It’ll be dedicated to high-altitude testing, icing and hail resistance. These tests are planned to occur this summer in Canada, Gordon Follin, Catalyst Engineering general manager said. Then, in addition to the 10 engines scheduled to be developed for the certification process, 3 others will be delivered to Cessna to support the Denali flight tests, the first of which should be delivered in late 2018.

The Cessna Denali is currently the only platform to be equipped with the Catalyst, but it is expected GE will announce more applications for its 850-1600shp family in the years to come. These new announcements should accelerate the company’s investments in the Czech Republic. GE is planning on building another plant in the country in case the production ramps up, but details about its location remain to be finalized.

Written by ADIT – The Bulletin and republished with permission.