A Century of Dominance

Lycoming and Continental engines have been the foundation of general aviation since the early 20th century, with Lycoming debuting in 1929 and Continental shortly after. These American-made engines, characterized by their air-cooled, horizontally-opposed piston configurations, powered the majority of post-WWII general aviation aircraft, including Cessnas and Pipers.

Tried and Tested Powerplants

Models like the Lycoming O-320/O-360 and the Continental O-200/IO-550 remain go-to choices for certified four- and six-seat aircraft. Known for their rugged design, reliability, and industry-wide support, these engines continue to be used in IFR-capable aircraft like the Cessna 172 and Cirrus SR22.

A Different Kind of Power

Austrian manufacturer ROTAX first entered aviation through ultralights and quickly moved into Light Sport Aircraft (LSA). The ROTAX 912 ULS, with only 100HP, is lighter and more efficient than its legacy counterparts, making it ideal for LSAs. Over time, ROTAX expanded with models like the 914 UL and the turbocharged 915iS and 916iS/c.

Innovation Over Bulk

ROTAX engines use liquid and air cooling, and many can run on MOGAS or UL 94, offering flexibility and reduced operational costs. Although they currently max out at 160HP, their lower weight and advanced engineering hint at potential scalability for the general aviation market.

Technical Comparison Table

Here’s a side-by-side look at key specs, showcasing differences in weight, cooling, turbocharging, fuel options, and time between overhauls (TBO):

ROTAX Efficiency Shines

The ROTAX 912 ULS burns just 4–5 gallons per hour at cruise, compared to 12–18 GPH in engines like the IO-540. This makes ROTAX a compelling option for time-builders, training operations, and pilots with budget-conscious flying goals.

The Middle Ground: Lycoming O-360

The Lycoming O-360 remains a standout for its balance of power and efficiency. It’s a staple in Cessna 172R/S models and burns 8–10 GPH—making it a solid performer for cross-country and flight training missions.

Certified Aircraft (Part 23) vs Experimental/LSA

Legacy engines dominate certified aircraft markets, offering the horsepower and certification required for IFR, commercial, and multi-passenger operations. Meanwhile, ROTAX engines are king in the LSA and experimental world, where weight, flexibility, and fuel savings are prioritized.

Modern LSAs Built Around ROTAX

Aircraft like the Vashon Ranger R7, Bristell B23, and Sling TSi are engineered with ROTAX in mind—prioritizing modern avionics, carbon composite frames, low emissions, and smooth, quiet performance.

ROTAX-Powered Time Builders

Odyssey Pilot Hours operates both the JMB VL3 and Evektor Harmony—two aircraft powered by ROTAX 912 ULS. These models exemplify high-performance, fuel-efficient design.

• JMB VL3: A carbon-fiber speed machine with cruise speeds topping 200 KTAS (likely using a 915iS), perfect for efficient cross-country flying.
• Evektor Harmony: A stable, reliable trainer with metal construction, ideal for student pilots and instructors alike.

Market Share and Potential Expansion

ROTAX currently holds more than 80% of the LSA engine market in certain segments [7]. If FAA regulations evolve with the proposed MOSAIC rule (which may allow more LSA aircraft designs and capabilities), ROTAX is well-positioned to expand into higher horsepower categories and certified aircraft.

What the Future Holds

While Lycoming and Continental will continue to serve the needs of traditional certified aviation, ROTAX is evolving quickly. With each new engine iteration, it inches closer to being a viable option for more powerful, certified airframes—offering the next generation of pilots cleaner, lighter, and more cost-effective propulsion.

Legacy engines bring power, simplicity, and proven reliability to the skies. But ROTAX is challenging the status quo with innovation, efficiency, and agility. Whether you’re a time-builder, a recreational flyer, or a future commercial pilot, understanding both systems is crucial for making smart aircraft and engine decisions in the modern aviation era.

 [1] Lycoming Engines, “Company History. ” [Online].
Available: https://www.lycoming.com
[2] Continental Aerospace Technologies, “About Us. ” [Online]. Available: https://www.continental.aero
[3] BRP-Rotax, “Aviation Engines. ” [Online].
Available: https://www.flyrotax.com
[4] Federal Aviation Administration, “Type Certificate Data Sheets: Lycoming O-320 Series. ” [Online].
Available: https://drs.faa.gov
[5] Federal Aviation Administration, “Type Certificate Data Sheets: Continental O-200 and IO-550 Series.” [Online]. Available: https://drs.faa.gov[8] BRP-Rotax,
[6] BRP-Rotax GmbH & Co KG, Rotax 912/914 Series Installation Manual. Gunskirchen, Austria.
[7] R. Bertorelli, “ROTAX Dominates LSA Market, ” AVweb, Aug. 2020. [Online]. Available: https://www.avweb.com

[8] BRP-Rotax, “Rotax 916 iS/c Launch Specifications. ” [Online]. Available: https://www.flyrotax.com
[9] BRP-Rotax GmbH & Co KG, Rotax 912 ULS Pilot Operating Handbook. Gunskirchen, Austria.
[10] Cirrus Design Corporation, SR22 Pilot Operating Handbook. Duluth, MN, 2020. Also: Piper Aircraft, Inc., PA-32 Pilot Operating Handbook. Vero Beach, FL.
[11] Aircraft Owners and Pilots Association, “Maintenance Guides on GA Engines. ”
[Online]. Available: https://www.aopa.org
[12] ULPower Aero Engines, “Technical Specifications. ” [Online]. Available: https://www.ulpower.com
[13] Experimental Aircraft Association, “Engine Guides.” [Online]. Available: https://www.eaa.org
[14] Textron Aviation Inc., Cessna 172S Pilot Operating Handbook. Wichita, KS, 2020.