ULPower Aero Engines

ULPower Aero Engines is a Belgian aircraft-engine manufacturer focused on piston powerplants for ultralight, light sport, experimental, kit-built and selected rotorcraft applications. The company emerged from a practical engineering problem rather than from a conventional aerospace-industrial program. In 2001, its future founding partners were asked to address an installation involving a Jabiru engine in a helicopter. They concluded that the engine was undersized for the application and chose to develop a new powerplant from the ground up. The founders brought experience from professional automotive competition, including engine design, development and production associated with Dakar Rally programs. Their automotive background also contributed to the development of a proprietary electronic control unit. The resulting concept emphasized a relatively simple architecture, low parts count, ease of maintenance, high power-to-weight ratio and low ownership cost. Additional design objectives included direct drive, air cooling, electronic engine management and the ability to use both aviation gasoline and specified grades of automotive gasoline containing ethanol. Development produced a prototype based on the architecture that later became the UL260i. The first recorded aircraft installation was in a Lambert Mission 106, with initial flight testing taking place in December 2005. Following ground and flight testing, the project was formalized as ULPower Aero Engines in March 2006, and series production began toward the end of that year. The company’s range is built around modular, horizontally opposed engine families. The engines use a common bore dimension, while different stroke lengths and cylinder counts create the principal displacement groups. The four-cylinder 260 and 350 families use 74 mm and 100 mm strokes respectively, while the six-cylinder 3900 cc and 5200 cc families extend the same modular idea to larger experimental and kit-built aircraft. Across the range, ULPower engines are direct-drive, air-cooled and equipped with multiport fuel injection and FADEC-style electronic engine management. The published fuel capability includes avgas grades such as 100LL and UL91, together with automotive gasoline up to the specified ethanol limit and required octane rating. The UL260i became the company’s initial series product and was installed in a number of light aircraft, including aircraft associated with Fly Synthesis, Zenair, Just Aircraft, Dyn’Aéro and Hannuman. In 2009, ULPower broadened the four-cylinder offering with the higher-output UL260iS and the larger UL350i/iS. The company also developed the inverted-oil-system UL260iSA in cooperation with the Twister Aerobatics Team, which needed a more powerful engine for inverted aerobatic operation in the Silence Twister. Market-specific variants included the UL260iF and UL350iF for French applications, particularly gyrocopters; the UL350iF was subsequently discontinued. The six-cylinder range introduced in 2013 was intended for larger non-certified aircraft that might otherwise use engines in the Lycoming O-320 or O-360 class, or corresponding clones. In 2017, Sonex Aircraft made four-cylinder ULPower engines a standard factory-supported alternative for its enlarged B-model aircraft. These applications illustrate ULPower’s market position: it is not principally a mass-market certified-airliner engine supplier, but a specialist manufacturer serving builders and operators who value compact installation, electronic engine control, low weight and a broad fuel strategy.

ULPower’s origins date to 2001, when a group of Belgian engineers and automotive specialists were asked to solve an engine-installation problem on a helicopter equipped with a Jabiru engine. The existing engine was considered too small for the intended application. Rather than modifying that installation indefinitely, the partners decided to design a new aircraft engine from first principles. The founding group included Nicolas Josson of ROPA.BE and Lionel and Pascal D’Hondt of DR Tuning. ROPA.BE contributed metal turning and milling capabilities for engine components, while DR Tuning brought experience from motor racing. The partners also had backgrounds in professional automotive rally work, including the design, development and production of engines for Dakar Rally programs. This experience influenced the proposed aircraft-engine architecture, particularly its focus on mechanical simplicity, limited parts count, serviceability and power relative to weight. A proprietary electronic control unit developed from their automotive experience became an important part of the project. The intended engine was to use electronic engine management, direct drive and air cooling, while supporting both aviation gasoline and appropriately specified automotive gasoline. These aims were combined with an objective of reducing ownership and maintenance burdens for operators of light aircraft. After several years of prototype construction and testing, the first UL260i was installed in a Lambert Mission 106. Its initial flight tests were conducted in December 2005. The successful progression from ground testing to flight testing led to the formal creation of ULPower Aero Engines in March 2006. Series production began later that year, establishing the company as a specialist supplier to the light-aircraft sector. The UL260i was subsequently installed in several light aircraft types, including the Fly Synthesis Storch, Zenair Zodiac CH601, Just Escapade, Dyn’Aéro MCR01 and Hannuman X-Air. These installations helped demonstrate the engine’s intended role in aircraft where low mass, compact packaging and uncomplicated operation were important considerations. In 2009, the company expanded beyond the original UL260i with the UL260iS and UL350i/iS. The UL260iS offered a higher output than the original model, while the UL350 family used a longer stroke to provide greater displacement and power. Around the same period, the Twister Aerobatics Team sought an engine capable of providing more power than its existing Jabiru 2200 and of operating during inverted flight. Cooperation between the team and ULPower resulted in the UL260iSA, which incorporated a fully inverted oil system. ULPower also offered versions adapted to specific French-market requirements. The UL260iF was derived from the UL260iS, and the UL350iF was developed from the UL350iS for applications including gyrocopters. The UL350iF is no longer available. In 2013, ULPower expanded its modular engine concept into six-cylinder products in 3900 cc and 5200 cc configurations. These engines were aimed at larger experimental and kit-built aircraft, including aircraft in a power category commonly served by Lycoming O-320 and O-360 engines or their derivatives. The company’s modular approach uses a common bore across its families, with stroke and cylinder count determining the main displacement groups. In 2017, Sonex Aircraft introduced enlarged B-model aircraft with additional engine-installation options. Four-cylinder ULPower engines became a standard factory-supported alternative for those aircraft, giving the Belgian manufacturer a recognized installation path within the experimental-aircraft market. ULPower’s documented product strategy has therefore developed from a single four-cylinder prototype into a family of electronically managed, air-cooled, direct-drive engines for light aircraft, aerobatic aircraft, gyrocopters and larger experimental aircraft.

• 2017

  ULPower becomes a supported Sonex B-model option

  [1]ULPower Aero Enginesen.wikipedia.org

  Sonex Aircraft introduced B models with more engine choices, including four-cylinder ULPower engines as a standard factory-supported alternative.

• 2013

  Six-cylinder engine family introduced

  [1]ULPower Aero Enginesen.wikipedia.org

  The product line expanded to six-cylinder engines in 3900 cc and 5200 cc configurations for larger experimental and kit-built aircraft.

• 2009

  Four-cylinder range expanded

  [1]ULPower Aero Enginesen.wikipedia.org

  ULPower introduced the UL260iS and UL350i/iS families, adding higher-output and larger-displacement options.

• 2009

  UL260iSA developed for inverted aerobatics

  [1]ULPower Aero Enginesen.wikipedia.org

  Cooperation with the Twister Aerobatics Team led to the UL260iSA with a fully inverted oil system.

• 2006

  ULPower Aero Engines formally established

  [1]ULPower Aero Enginesen.wikipedia.org

  The project was placed into a formal company structure in March, with series production commencing by the end of the year.

• 2005

  First UL260i flight tests

  [1]ULPower Aero Enginesen.wikipedia.org

  A UL260i was installed in a Lambert Mission 106, and initial flight testing took place in December.

• 2001

  Project begins after helicopter-engine installation problem

  [1]ULPower Aero Enginesen.wikipedia.org

  The future founding partners began developing a new engine after concluding that a Jabiru engine installed in a helicopter was too small for the intended application.

A specialist light-aircraft engine manufacturer emphasizing low weight, direct-drive simplicity, electronic engine management, maintainability, fuel flexibility and performance for non-certified and light-aircraft applications.

• Four-cylinder aircraft engine · 2005

  UL260i

  The UL260i was ULPower’s first principal production engine and the product used for the company’s initial aircraft flight tests. It is a direct-drive, air-cooled, horizontally opposed piston engine with electronic engine management and a 74 mm stroke. The approximately 72 kW, or 97 hp, model was installed in a range of ultralight and light aircraft, including the Lambert Mission 106, Fly Synthesis Storch, Zenair Zodiac CH601, Just Escapade, Dyn’Aéro MCR01 and Hannuman X-Air.

• Four-cylinder aircraft engine · 2009

  UL260iS

  The UL260iS is a higher-output development of the 260 family. It retains the family’s compact, air-cooled and direct-drive concept while providing approximately 80 kW, or 107 hp. Its 74 mm stroke also distinguishes it from the longer-stroke 350 family. The engine served as the basis for the UL260iF adaptation and contributed to the broader range of light-aircraft installation options.

• Inverted-operation aerobatic aircraft engine · 2009

  UL260iSA

  The UL260iSA was developed with the Twister Aerobatics Team for the Silence Twister. It was designed to provide more power than the team’s original Jabiru 2200 while supporting inverted aerobatic operation. Its principal distinguishing feature is a fully inverted oil system. The engine is rated at approximately 80 kW, or 107 hp, and is a specialized derivative of the UL260 family.

• Four-cylinder aircraft engine · 2009

  UL350i/iS

  The UL350i and UL350iS are larger-displacement four-cylinder engines created by increasing the stroke from the 260 family’s 74 mm to 100 mm. The family produces approximately 93 kW, or 125 hp, in the cited configuration. It extends ULPower’s modular architecture to aircraft requiring more output while retaining the direct-drive, air-cooled and electronically managed design approach.

• Market-specific aircraft engine variant

  UL260iF

  The UL260iF was an adaptation of the UL260iS intended specifically for the French market. It was rated at approximately 74 kW, or 100 hp, and formed part of ULPower’s effort to tailor its light-aircraft engine range to local application requirements. It is distinct from the UL260iSA, which was developed for inverted aerobatic operation.

• Gyrocopter-oriented aircraft engine variant

  UL350iF

  The UL350iF was a French-market adaptation based on the UL350iS and was intended particularly for gyrocopter applications. Its cited output was approximately 90 kW, or 120 hp. The model is documented as no longer available, making it a discontinued or withdrawn member of the ULPower family.

• Six-cylinder aircraft engine · 2013

  UL3900

  The 3900 cc six-cylinder family extends ULPower’s modular architecture to larger experimental and kit-built aircraft. Six-cylinder engines share the company’s horizontally opposed, air-cooled and direct-drive concept and are offered with compression and fuel-grade choices. They target aircraft that require more displacement than the four-cylinder 260 and 350 families.

• Six-cylinder aircraft engine · 2013

  UL5200

  The 5200 cc six-cylinder family is the larger documented ULPower displacement group. It is intended for experimental and kit-built aircraft in a power class often associated with Lycoming O-320/O-360-sized installations or comparable engines. Different compression configurations require corresponding minimum fuel grades, while the general architecture remains direct drive, air cooled and electronically managed.

• 2017

  Factory-supported Sonex B-model installationProduct launch

  Background

  Sonex Aircraft introduced B models with a larger fuselage and additional engine-installation possibilities.

  Action taken

  Four-cylinder ULPower engines were included as a standard factory-supported alternative.

  Aftermath

  The arrangement gave ULPower a documented supported installation in a prominent experimental-aircraft family.

  Source

• 2013

  Expansion into six-cylinder enginesProduct launch

  Background

  Larger experimental and kit-built aircraft required more displacement than the company’s four-cylinder range could provide.

  Action taken

  ULPower added six-cylinder engines in 3900 cc and 5200 cc variants, with compression options tied to different fuel requirements.

  Aftermath

  The company extended its modular engine strategy into a larger aircraft segment commonly served by Lycoming-class installations.

  Source

• 2009

  Launch of UL260iS and UL350i/iSProduct launch

  Background

  The initial UL260i created a base for a broader family of light-aircraft engines with different output requirements.

  Action taken

  ULPower introduced the higher-output UL260iS and the longer-stroke UL350i/iS family.

  Aftermath

  The range gained both a higher-output version of the 260 architecture and a larger-displacement four-cylinder option.

  Source

• 2009

  Development of the UL260iSA inverted-oil variantProduct launch

  Background

  The Twister Aerobatics Team needed more power than its Jabiru 2200 and required an engine capable of inverted operation.

  Action taken

  ULPower cooperated with the team to develop the UL260iSA with a fully inverted oil system.

  Aftermath

  The 260 family gained a specialized aerobatic application for the Silence Twister.

  Source

• 2001

  Develop a new aircraft engine rather than modify an undersized installationStrategy

  Background

  The founding partners were asked to address a Jabiru engine installation in a helicopter and judged the existing engine too small for the application.

  Action taken

  They chose to design a new powerplant from scratch, with targets including low weight, simple construction, maintainability, electronic control, direct drive, air cooling and fuel flexibility.

  Aftermath

  The decision became the foundation of the ULPower project and ultimately led to the company’s formal establishment and series production.

  Source

1. 1ULPower Aero Enginesen.wikipedia.org