2025 in Review: Propulsion

In February, Pratt & Whitney received FAA certification for the upgraded PW1100G Advantage geared turbofan that powers the Airbus A320neo. A comprehensive core improvement package targeting greater performance while addressing nagging durability issues, the Advantage includes increased airflow in the core to reduce operating temperatures and an improved hot section to double time on wing.

Venus Aerospace in May conducted the first ground-launched test flight of a vehicle powered by a rotating detonation rocket engine (RDRE) from Spaceport America in New Mexico. This was followed by a strategic investment in the startup by Lockheed Martin Ventures. Venus is developing the Venus Detonation Rocket, which combines the RDRE with a ramjet to propel a vehicle from a standing start to Mach 6.

In June, GE Aerospace formally teamed with Kratos Defense & Security Solutions to develop small turbofans of up to 1,500 lb. thrust for the next generation of uncrewed aircraft. The first engine—the 800-lb.-thrust GEK800 for cruise missiles—completed altitude testing in October. In November, GE announced it was developing a small turbofan for midsize collaborative combat aircraft.

A Boeing engineering team employed out-of-the-box thinking—including use of a powerful leaf blower—to investigate and resolve a resonance that caused the premature fatigue failure of a load-transferring component attached to the 777-9’s GE Aerospace GE9X engines. Investigation of the puzzling failure and subsequent redesign of the thrust link enabled Boeing to resume flight tests after a five-month hiatus.

In July, Rolls-Royce froze the design of a smaller demonstrator version of the UltraFan geared turbofan as part of plans to reenter the single-aisle market in the 2030s. Ground testing will be conducted under the EU Clean Aviation research program’s Unified (Ultra Novel and Innovative Fully Integrated Engine Demonstrations) project. The UltraFan 30 is aimed at the thrust range above 30,000 lb.

In September, Honeywell unveiled plans to develop the HON1600, a scalable, low-cost engine family covering the 800-1,600-lb.-thrust class to compete in the collaborative combat aircraft market. The engine is designed for high maneuverability and operation at altitudes up to 40,000 ft. The core engine has been demonstrated at rated thrust.

GE Aerospace ran a modified Passport business jet engine in hybrid-electric mode in October, marking a key step toward development of the Open Fan propulsion system under CFM International’s Revolutionary Innovation for Sustainable Engines (RISE) initiative to develop technology for next-generation single-aisle aircraft. The hybrid elements include motor-generators on the high-pressure and low-pressure spools along with offboard motor controllers.

The first Boeing 787-9 with upgraded Rolls-Royce Trent 1000 XE engines was delivered to Lufthansa in November. The XE features revised high-pressure turbine blades with 40% additional cooling airflow that, along with a revised cooling hole pattern, enables the blades to survive significantly longer.

Safran is planning a range of new, low-cost CCA powerplants dubbed the M15, M30 and M50. Few details have been revealed, although the initial series will cover thrust ranges of 3,300 lb., 6,600 lb. and 11,000 lb.

Boom Supersonic in December revealed a $1.25 billion launch order for an industrial gas turbine version of its in-development Symphony supersonic engine to power artificial intelligence data centers. In parallel, the startup completed a $300 million funding round it says is sufficient to complete development of the Symphony and build the initial Overture M1.7 airliner.