Rolls-Royce engineers are researching which sensor-data patterns could prove significant in indicating possible future condition issues with Pearl 15 engines designed to power Bombardier Global 5500 and Global 6500 business jets, in a continuing effort to make the Pearl 15’s engine vibration health monitoring unit (EVHMU) ever more effective.
Dr. Dirk Geisinger, R-R’s director of business aviation and chairman of Rolls-Royce Deutschland, told AIN the company is using its Pearl 15 sensor-data pattern research to train artificial intelligence (AI) algorithms at the heart of the software that controls the EVHMU’s engine-parameter monitoring and broadcasting capability. Geisinger likened the EVHMU-training process to the ReCaptcha function that asks personal-computer users browsing any of a host of websites to select all those boxes in a photographic grid which display a certain feature—say, a storefront or a traffic light. Although ReCaptcha does this under the guise of having each website viewer confirm that ‘I’m Not A Robot,’ in reality major technology firms use the function to help train the AIs they are developing to recognize different patterns, he said.
Geisinger said the monitoring capability the EVHMU provides has led the company to call the Pearl 15 its “next-generation intelligent engine.” The Pearl 15 EVHMU’s data-monitoring and broadcasting capability allows R-R to incorporate engine health monitoring diagnostics in the EVHMU and provide bi-directional communication between the EVHMU and the operator, or R-R, enabling them easily to reconfigure Pearl 15 engine-monitoring features remotely from ground stations.
In practice, that will allow R-R or the operator to reconfigure the Pearl 15 EVHMU’s software to monitor different parts of the engine and its accessories in near-real-time by selecting from a variety of software filters provided by the AI controlling EVHMU functioning, according to Geisinger. The Pearl 15 EVHMU can monitor 9,000 different parameters indicating the condition of different parts of the engine and its line replaceable units (LRUs), “but not all at the same time,” he said. So each EVHMU software filter specifies a different sub-set of data parameters to monitor. By doing so, the EVHMU is able to monitor every different vibration that occurs in any Pearl 15 part and LRU, and also monitor operating temperatures and pressures throughout the engine.
Each filter selected can then broadcast relevant engine-parameter data to R-R or the operator as soon as the Global 5500 or Global 6500 has landed. If the operator chooses to have R-R maintain its Pearl 15s under the OEM’s fixed-price CorporateCare Enhanced power-by-the-hour coverage—as R-R thinks many operators will, though it also offers traditional, less comprehensive time-and-maintenance coverage for the Pearl 15—then R-R will use the engine-diagnostics data it receives to provide preventive maintenance for the engines.
Geisinger said the CorporateCare Enhanced package—which R-R introduced earlier this year specifically for the Pearl 15 and the BR710 versions powering the Gulfstream V, the Gulfstream G550 and the Bombardier Global Express—is even more comprehensive than the CorporateCare coverage R-R previously offered. The Enhanced package adds MRO coverage for the engine’s nacelle, thrust reverser and pneumatic dual-action actuator, as well as coverage of the composite parts in the engine and coverage for any part-corrosion. “It covers the whole integrated powerplant rather than just the core engine, as in the past,” he said.
The Pearl 15 EVHMU is the most advanced and capable engine health monitoring unit that Rolls-Royce has ever developed for any engine. and in the future, R-R will install EVHMUs of similar design and specification in all of its commercial and bizav engine models, according to Geisinger. Rolls-Royce Control Systems in Birmingham, England developed the EVHMU and is manufacturing the units.
Approximately “the size of two larger laptops” joined together, the Pearl 15 EVHMU is attached to the top of the engine, said Geisinger. To ensure the Pearl 15’s operational safety and security by preventing any hacker taking operational control of the engine remotely through the EVHMU’s two-way broadcast function, R-R has designed the EVHMU to be entirely separate “physically and electronically” from the engine’s full authority digital engine control (Fadec) computer, said Geisinger. This makes the EVHMU unable to communicate any data whatsoever to the Fadec unit: all data flow between the two units is entirely unidirectional. The engine-parameter data generated by the sensors flows from the Fadec computer into the EVHMU, where the data is filtered and analyzed by the EVHMU’s artificial intelligence.
Geisinger confirmed that the Pearl 15 EVHMU is capable of broadcasting engine-parameter data to the ground in real-time, “but the industry isn’t ready yet [for it] from a technological and transactional point of view. The broadcasting piece depends at the end of the day on what the airframer and its customers want to have, so it’s not our call. So Rolls-Royce is talking to airframers to see the different concepts for the beauty contest” for live air-to-ground broadcasting of engine-parameter data, he said. When it sees “which concept wins,” R-R will then design its EVHMU in-flight, real-time broadcast capability so that it fits seamlessly with that concept.
As of mid-September, Pearl 15 engine testing had accumulated more than 3,700 hours and more than 13,000 cycles of ground and flight-testing, according to Geisinger. “We’re really proud of how mature the engine is,” he said. During the design-testing program, the Pearl 15 was “almost too good,” because none of the severe tests to which the development engines were subjected caused enough damage for Rolls-Royce to think any design improvement was needed. “So we have really great confidence in a reliable product out of the box” when the Pearl 15 enters service on the Global 5500 and Global 6500 later this year—a schedule R-R and Bombardier remain confident of meeting.