The Rolls-Royce Turbomeca RTM322 is a

turboshaft A turboshaft engine is a form of gas turbine that is optimized to produce shaftpower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the exhaust ...

engine produced by Safran Helicopter Engines. It was originally conceived and manufactured by

Rolls-Royce Turbomeca Limited Rolls-Royce Turbomeca Limited (RRTM) is a joint venture between British aero-engine manufacturer Rolls-Royce plc (UK) and French helicopter engine specialist Safran Helicopter Engines (formerly known as Turbomeca). It manufactured aero-engines ...

, a joint venture between

Rolls-Royce plc Rolls-Royce Holdings plc is a British multinational aerospace and defence company incorporated in February 2011. The company owns Rolls-Royce, a business established in 1904 which today designs, manufactures and distributes power systems for ...

and

Turbomeca Safran Helicopter Engines, previously known as Turbomeca, is a French manufacturer of low- and medium-power gas turbine turboshaft engines for helicopters. The company also produces gas turbine engines for aircraft and missiles, as well as turbin ...

(now

Safran Helicopter Engines Safran Helicopter Engines, previously known as Turbomeca, is a French manufacturer of low- and medium-power gas turbine turboshaft engines for helicopters. The company also produces gas turbine engines for aircraft and missiles, as well as turbin ...

). The engine was designed to suit a wide range of military and commercial

helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes ...

designs. The RTM322 can also be employed in maritime and industrial applications. The Safran Aneto is a later development targeted for the super-medium and heavy

s, developed by

, unveiled at London's Helitech on 3 October 2017 and covering the range.

Development

It was designed for the Hughes AH-64 Apache and

Sikorsky UH-60 Blackhawk The Sikorsky UH-60 Black Hawk is a four-blade, twin-engine, medium-lift utility military helicopter manufactured by Sikorsky Aircraft. Sikorsky submitted the S-70 design for the United States Army's Utility Tactical Transport Aircraft System ( ...

, competing with the

General Electric T700 The General Electric T700 and CT7 are a family of turboshaft and turboprop engines in the class. Design and development In 1967, General Electric began work on a new turboshaft engine demonstrator designated the "GE12" in response to US Army i ...

and the

Pratt & Whitney Canada PW100 The Pratt & Whitney Canada PW100 aircraft engine family is a series of turboprops manufactured by Pratt & Whitney Canada. Pratt & Whitney Canada dominates the turboprops market with 89% of the turboprop regional airliner installed base in 2016, ...

. The partners shared equally the £100 million development costs, Rolls-Royce makes the

turbine A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced by a turbine can be used for generating e ...

s, the

combustor A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, combustion chamber or flame holder. In a gas turbine engine, the ''combustor'' or combustion chamber is fed ...

, and the inlet particle separator while Turbomeca produces the axial-

centrifugal compressor Centrifugal compressors, sometimes called impeller compressors or radial compressors, are a sub-class of dynamic axisymmetric work-absorbing turbomachinery. They achieve pressure rise by adding energy to the continuous flow of fluid through th ...

and

intake An intake (also inlet) is an opening, structure or system through which a fluid is admitted to a space or machine as a consequence of a pressure differential between the outside and the inside. The pressure difference may be generated on the ins ...

. It first ran on 15 December 1984, with eight bench

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototyp ...

s for 30,000 cycles and 13,000 test hours, and four for flight tests, initially aiming for a 1987

certification Certification is the provision by an independent body of written assurance (a certificate) that the product, service or system in question meets specific requirements. It is the formal attestation or confirmation of certain characteristics of a ...

. The first order for the RTM322 was received in 1992 to power 44

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...

AugustaWestland Merlin HM1s which subsequently entered service in 1998. Over 1,100 engines are in service, having logged over one million flight hours, powering 60% of the AW101 fleet and 80% of in-service NH90s. In 2013, Turbomeca (part of the

Safran Group Safran S.A. is a French multinational company that designs, develops and manufactures aircraft engines, rocket engines as well as various aerospace and defense-related equipment or their components. It was formed by a merger between SNECMA and ...

, and now known as Safran Helicopter Engines) acquired the entire programme, becoming responsible for both production and product support. Safran Helicopter Engines has since developed a new engine derived from the RTM322, known as the Aneto.

Safran Aneto

The first 2,500 shp -1K was selected to power the Leonardo AW149 and Leonardo AW189K twin to extend its capabilities, it flew in March 2017 and is scheduled to be introduced in the fourth quarter of 2018. The more powerful 3,000+ shp “Dash 3” should appear in the early 2020s and will feature a new compressor and hot section. The required documentation should be handled to the

EASA The European Union Aviation Safety Agency (EASA) is an agency of the European Union (EU) with responsibility for civil aviation safety. It carries out certification, regulation and standardisation and also performs investigation and monitori ...

in early 2019 for a second quarter certification. By October 2018, the programme had accumulated 4,000 hours, including 105 hours of flight time. Sikorsky is considering re-engining its CT7-powered S-92. The Aneto-1K was added on the RTM 322

type certificate A type certificate signifies the airworthiness of a particular category of aircraft, according to its manufacturing design (''type design''). It confirms that the aircraft of a new type intended for serial production, is in compliance with applica ...

on 12 December 2019.

Design

As an RTM322 variant, the Aneto is a two spool turboshaft with a three stage axial compressor and a single stage centrifugal compressor turning at 36,300rpm, a reverse flow annular combustor, a two stage gas generator

axial turbine An axial turbine is a turbine in which the flow of the working fluid is parallel to the shaft, as opposed to radial turbines, where the fluid runs around a shaft, as in a watermill. An axial turbine has a similar construction as an axial compressor ...

and a two stage axial power turbine with a forward transmission shaft turning at 21,000rpm. Fitted with an inlet

particle In the Outline of physical science, physical sciences, a particle (or corpuscule in older texts) is a small wikt:local, localized physical body, object which can be described by several physical property, physical or chemical property, chemical ...

separator, its accessory gearbox is driven by the gas generator and the engine is control by a

FADEC A full authority digital engine (or electronics) control (FADEC) is a system consisting of a digital computer, called an "electronic engine controller" (EEC) or "engine control unit" (ECU), and its related accessories that control all aspects of ai ...

. Built upon the Safran Tech 3000 technological demonstrator, it aims to gradually offer up to 15% better fuel economy over current competitors to improve

payload-range Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...

and offers 25% better

power density Power density is the amount of power (time rate of energy transfer) per unit volume. In energy transformers including batteries, fuel cells, motors, power supply units etc., power density refers to a volume, where it is often called volume p ...

than existing engines of same volume. Offered for new or for existing models, fewer scheduled maintenance tasks, longer maintenance intervals and health monitoring should improve

maintainability In engineering, maintainability is the ease with which a product can be maintained to: * correct defects or their cause, * Repair or replace faulty or worn-out components without having to replace still working parts, * prevent unexpected working ...

. Suited for 8–15 ton helicopters, it is developed from the RTM322: the -1K has a similar architecture but no common parts. Parts made by

additive manufacturing 3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer co ...

are used in the gyratory

combustion chamber A combustion chamber is part of an internal combustion engine in which the fuel/air mix is burned. For steam engines, the term has also been used for an extension of the firebox which is used to allow a more complete combustion process. Interna ...

and the inlet guide vane system. Compatible with

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two dif ...

and

distributed propulsion In aeronautics, Distributed propulsion is an arrangement in which the propulsive and related air flows are distributed over the aerodynamic surfaces of an aircraft. The purpose is to improve the craft's aerodynamic, propulsive and/or structural ...

systems, in cruise flight one of the two engines could be shut down and restarted when needed. In the AW189, it is offered along the incumbent General Electric CT7, needing minor changes to the top-deck structure and engine cowls. Exempted from U.S.

International Traffic in Arms Regulations International Traffic in Arms Regulations (ITAR) is a United States regulatory regime to restrict and control the export of defense and military related Military technology, technologies to safeguard National security of the United States, U.S. ...

, it could power the AW189's military derivative, the

AW149 The AgustaWestland AW149 is a medium-lift multi-role military helicopter developed by AgustaWestland, now Leonardo, launched in 2006. On 20 June 2011 AgustaWestland announced the AW189, a civilian development of the AW149, for service in 2013. ...

or a future

attack helicopter An attack helicopter is an armed helicopter with the primary role of an attack aircraft, with the offensive capability of engaging ground targets such as enemy infantry, military vehicles and fortifications. Due to their heavy armament they ...

based on its dynamic systems. Developed from a French Aviation Authority study, the Safran Power Pack Eco Mode on the Airbus Helicopters Racer allows it to shut down one of engines in cruise, lowering fuel consumption by 15%, and quickly and automatically reactivate it with an

electric starter A starter (also self-starter, cranking motor, or starter motor) is a device used to rotate (crank) an internal-combustion engine so as to initiate the engine's operation under its own power. Starters can be electric, pneumatic, or hydraulic. ...

to its maximum power for acceleration, landing or emergencies. The Aneto specific fuel consumption should be 10% better than the competing CT7s.

Applications

AgustaWestland Apache The AgustaWestland Apache is a licence-built version of the Boeing AH-64D Apache Longbow attack helicopter for the British Army Air Corps. The first eight helicopters were built by Boeing; the remaining 59 were assembled by Westland Helicopt ...

AgustaWestland AW101 The AgustaWestland AW101 is a medium-lift helicopter in military and civil use. First flown in 1987, it was developed by a joint venture between Westland Helicopters in the United Kingdom and Agusta in Italy in response to national requirement ...

NHIndustries NH90 The NHIndustries NH90 is a medium-sized, twin-engine, multi-role military helicopter. It was developed in response to NATO requirements for a battlefield helicopter which would also be capable of being operated in naval environments. The NH90 ...

* Also used in

Eurocopter X3 Airbus Helicopters SAS (formerly Eurocopter Group) is the helicopter manufacturing division of Airbus. It is the largest in the industry in terms of revenues and turbine helicopter deliveries. Its head office is located at Marseille Provence Ai ...

Aneto

* Leonardo AW149 * Leonardo AW189K: Aneto-1K, 2,500 shp; March 2017 first flight, fourth quarter of 2018 introduction. * Proposed for the

Airbus Helicopters X6 The Airbus Helicopters X6 is a design concept for a 19-seat twin-engined heavy lift helicopter to replace the Airbus Helicopters H225. Development was stopped in early 2018. Development In June 2015, Airbus Helicopters announced the start of a ...

(suspended) * Airbus Helicopters Racer high-speed demonstrator: Aneto-1X, 2,500 shp.

Specifications

References

External links

Rolls-Royce RTM322 page

Turbomeca RTM 322 page
* {{Joint development aeroengines 1990s turboshaft engines Rolls-Royce aircraft gas turbine engines Turbomeca aircraft engines Mixed-compressor gas turbines 2010s turboshaft engines