GE’s clean-sheet Catalyst turboprop engine, destined to power Cessna’s developmental Denali single, has taken a belated step toward entry into service with the first example now mounted on the wing of a testbed King Air. Product line leader David Kimball said the Catalyst’s innovative integrated prop engine and prop control system “worked seamlessly” during initial ground tests. First flight was previously expected in 2020, but COVID-19 delays pushed the schedule to the right.
The GE Catalyst program is a direct challenge to the legendary market dominance of Pratt & Whitney Canada’s PT6-A series, which entered service in 1964 and has powered no fewer than 70 different aircraft models. GE took its first swing at the PT6-A when it bought and modernized the former Czech Walter M601 into its H-series turboprop. But the Catalyst, launched in 2015, is a whole new challenger.
The 1.240 shp Catalyst, like the PT6-A, is a reverse-flow free turbine, meaning intake air flows through ducts and enters the engine at the rear, while exhaust flows from stacks at the front of the engine nacelle. But the similarity quickly dissipates from there. GE boasts that modern materials, 21st century production techniques and advanced computer controls provide 10% more cruise power than a comparable PT6-A; 20% less fuel burn resulting in lower emissions and greater efficiency; lighter weight; a single-lever power control and dual-channel full-authority digital engine control (FADEC).
For example, 3D printing (aka additive manufacturing) reduces weight and parts count. More than one-third of the Catalyst is made of additive components, in reducing parts count in one component from 855 to 12.