Niki Lauda, the Austrian-born Formula One race car driver who went on to win three F1 world driver’s championships for both Ferrari and McClaren in the 1970s and ’80s, was nicknamed “The Computer” because of his unique ability to detect and analyze technical problems in the cars he drove. He was also famously contrarian. When he walked away from Formula One the first time, in 1978, he reportedly said he was “tired of driving around in circles.” But not tired enough to found his own airline company, Lauda Air.
Lauda would have fit like a glove into the GE Aviation team responsible for breathing life into the “digital brain” of the Catalyst engine, where actual flying time has been invaluable to the process. As Simone Castellani, Controls, Fuel & Prop Leader at Avio Aero, puts it: “When you work in aviation, especially in private aviation, so close to the product, a license to fly is highly recommended. It gives you a passion for what you do and a real perspective on the product.”
Castellani knows what he’s talking about. Fascinated since age 3 by the planes he saw landing and taking off at the small airport he grew up near in Italy, he finally got his pilot’s license as an adult. Nowadays, whenever he can afford to take a break from testing the Full Authority Digital Engine Control with integrated propeller control, or FADEC (a.k.a. the “digital brain”), Castellani can hardly wait to climb into the cockpit.
It helps that for the last three years Castellani has worked closely with another pilot on the Catalyst engine—Brian Cozine, Head of Propeller Design for the Cessna Denali at McCauley, a subsidiary of Textron Aviation. “Even if Brian has been flying for over 20 years and has a lot more experience than I,” Castellani hastened to add.
The thing that got Cozine hooked on aviation was remote-controlled airplanes. Then, in high school, one of his teachers took him on real flight lesson. “That was probably when I fell in love with planes,” he said. “I like their structure—so robust yet so light and slender— as well as how they are built. Being a pilot and working in the aviation industry allows you to think of higher-level products, in line with what a pilot expects.”
Castellani, along with his team and the other Avio Aero teams responsible for designing and manufacturing (or in some cases 3D-printing) several engine’s modules, are currently in the testing phase. With the help of some legitimately revolutionary innovations, the Catalyst turboprop engine program—which will equip the brand new Cessna Denali from Textron Aviation—is on track to take to the sky in 2019. Considering that the engine was little more than a name on a piece of paper in 2015, and that the average development time for a new engine is about ten years, it’s a remarkably fast arc from idea to reality.
The beauty of the Catalyst’s digital brain is its simplicity. Instead of using one lever for engine power and another for propeller control, the standard arrangement on turboprops for the last 30 years, the FADEC with integrated propeller control directs the power management system through a single lever; sensors and smart actuation technologies process parameters like altitude, pressure, temperature, turbine and aircraft speed, and engine rpm all in one place. “Above all, it saves the pilot from the burden of continuously adjusting throttle demand and monitoring the various gauges in the cockpit during any taxi or flight phase, optimizing the flight experience and making it much more enjoyable,” Castellani explained.
Currently, the only place where the FADEC with integrated propeller control can be tested together with various engine actuation systems (i.e. propeller, oil and fuel) is Avio Aero’s so-called “wet rig” in Brindisi. Experts and professionals from all over the world have visited the wet rig, which integrates a fully representative propeller test bench that reproduces aerodynamic and hydraulic load throughout the entire flight envelope. (It’s called a wet rig because it allows fluids to flow through the engine during testing.)
There are two test rooms inside the wet rig: The first is dedicated to the engine’s accessory gearbox, the second to the power gearbox (PGB), which moves the propeller. McCauley is one of the world’s largest manufacturers and designers of aeronautical propellers with over 500 models in production and in use on some of the most legendary propeller airplanes—Beechcraft, Cessna, Piper, Stoddard Hamilton and many more. This is why Cozine was intensely interested in the PGB test room—he wanted to see how the propellers his team has made for the Denali would perform.
“The Denali 5-blade propeller has been designed with composite materials that give it perfect aerodynamics that can be integrated with both the aircraft and the engine to offer excellent performance,” he said.
“The wet rig in Brindisi is a unique rehearsal room world-wide,” Castellani noted while standing with Cozine in front of a throttle setup that would not seem out of place on an episode of Star Trek. “Here we verify the ability of the FADEC to program and manage oil, fuel, and air flows, testing the operation of the entire engine system at any real operating speed, as it is electronically simulated in real time. The simulator interacts with the FADEC as it monitors and controls the various sensors and actuators, translating electrical inputs into electrical and mechanical outputs which regulate the pitch of the propeller as well as the flow of fuel and air during each phase of flight, or under any weather condition recreated on the test bench.”
No stranger to robust testing technology, Cozine was impressed by the accuracy of Avio Aero’s wet rig once he got to see it in action. While in Brindisi, he focused his attention on four key elements: speed, thrust, noise, and weight.
“Textron Aviation and McCauley want to make sure that the wet rig provides useful answers in terms of thrust and power expressed in horsepower, or that it confirms the synchrony between the two,” he said. “For the first time, after three years of intense collaboration with the Avio Aero team for Denali, I got a satisfactory response on the joint operation of the engine and propeller.”
It was also not lost on him that, for the first time in turboprop history, the wet rig has made it possible to simulate the human experience of real flight inside a test room.
“I hope that my team understands the wide range of possibilities offered by the wet rig simulation and how much the operating conditions reproduced here are impossible or very expensive to reproduce in the real world,” Cozine said.
Or as Niki Lauda might have observed, so much for driving around in circles.