Rolls-Royce Gem

Last updated

Gem
Rolls Royce Gem HMW.JPG
Rolls-Royce Gem at The Helicopter Museum (Weston)
Type Turboshaft
National origin United Kingdom
Manufacturer Rolls-Royce Limited
Major applications Westland Lynx

The Rolls-Royce Gem is a turboshaft engine developed specifically for the Westland Lynx helicopter in the 1970s. The design started off at de Havilland Engine division (hence the name starting with "G") and passed to Bristol Siddeley as the BS.360. Rolls-Royce bought out Bristol Siddeley in 1966 and after it dropped the Bristol Siddeley identity the engine became the RS.360. [1]

Contents

Design and development

The Gem's three-shaft engine configuration is rather unusual for turboshaft/turboprop engines. Basic arrangement is a four-stage axial LP (Low Pressure) compressor, driven by a single stage LP turbine, supercharging a centrifugal HP (High Pressure) compressor, driven by a single stage HP turbine. Power from a two-stage free (power) turbine is delivered to the load via a third shaft. A reverse flow combustor is featured. [2]

The Gem 42 develops 1,000 shp (750 kW) at Take-off, Sea Level Static, ISA, but the Maximum Contingency Rating (MCR) is 1,120 shp (840 kW).

Until recently all versions of the Lynx have been Gem powered. However, now that Rolls-Royce owns Allison, it has been marketing the more modern LHTEC T800, developed jointly with Honeywell.

Applications

Engines on display

Specifications (Gem 42)

Rolls-Royce Gem on display at the Midland Air Museum RRGem.JPG
Rolls-Royce Gem on display at the Midland Air Museum

Data fromRolls-Royce [3]

General characteristics

Components

Performance

See also

Comparable engines

Related lists

Related Research Articles

<span class="mw-page-title-main">Bristol Proteus</span> 1940s British turboprop aircraft engine

The Bristol Proteus was the Bristol Engine Company's first mass-produced gas turbine engine design, a turboprop that delivered just over 4,000 hp (3,000 kW). The Proteus was a reverse-flow gas turbine. Because the second turbine drove no compressor stages, but only the propeller, this engine was classified as a free-turbine. It powered the Bristol Britannia airliner, small naval patrol craft, hovercraft and electrical generating sets. It was also used to power a land-speed record car, the Bluebird-Proteus CN7. After the merger of Bristol with Armstrong Siddeley the engine became the Bristol Siddeley Proteus, and later the Rolls-Royce Proteus. The Proteus was to have been superseded by the Bristol Orion which would have given a Britannia a 75% increase in power for cruising faster.

<span class="mw-page-title-main">Rolls-Royce Pegasus</span> 1950s British turbofan aircraft engine

The Rolls-Royce Pegasus is a British turbofan engine originally designed by Bristol Siddeley. It was manufactured by Rolls-Royce plc. The engine is not only able to power a jet aircraft forward, but also to direct thrust downwards via swivelling nozzles. Lightly loaded aircraft equipped with this engine can manoeuvre like a helicopter. In particular, they can perform vertical takeoffs and landings. In US service, the engine is designated F402.

<span class="mw-page-title-main">Rolls-Royce Turbomeca RTM322</span> 1980s British/French turboshaft engine

The Rolls-Royce Turbomeca RTM322 is a turboshaft engine currently produced by Safran Helicopter Engines. The RTM322 was originally conceived and manufactured by Rolls-Royce Turbomeca Limited, a joint venture between Rolls-Royce and Turbomeca. The engine was designed to suit a wide range of military and commercial helicopter designs. The RTM322 can also be employed in maritime and industrial applications.

<span class="mw-page-title-main">Rolls-Royce Olympus</span> Supersonic turbojet engine with afterburner

The Rolls-Royce Olympus was the world's second two-spool axial-flow turbojet aircraft engine design, first run in May 1950 and preceded only by the Pratt & Whitney J57, first-run in January 1950. It is best known as the powerplant of the Avro Vulcan and later models in the Concorde SST.

<span class="mw-page-title-main">LHTEC T800</span>

The LHTEC T800 is a turboshaft engine for rotary wing applications. It is produced by the LHTEC, a joint venture between Rolls-Royce and Honeywell. The commercial and export version is the CTS800. The engine was primarily developed for the United States Army's cancelled RAH-66 Comanche armed reconnaissance helicopter, but has found use in other applications.

<span class="mw-page-title-main">Rolls-Royce Dart</span> 1940s British turboprop aircraft engine

The Rolls-Royce RB.53 Dart is a turboprop engine designed and manufactured by Rolls-Royce Limited. First run in 1946, it powered the Vickers Viscount on its maiden flight in 1948. A flight on July 29 of that year, which carried 14 paying passengers between Northolt and Paris–Le Bourget Airport in a Dart-powered Viscount, was the first regularly scheduled airline flight by a turbine-powered aircraft. The Viscount was the first turboprop-powered aircraft to enter airline service - British European Airways (BEA) in 1953.

<span class="mw-page-title-main">Rolls-Royce Clyde</span> 1940s British turboprop aircraft engine

The Rolls-Royce RB.39 Clyde was Rolls-Royce's first purpose-designed turboprop engine and the first turboprop engine to pass its civil and military type-tests.

<span class="mw-page-title-main">Napier Gazelle</span> 1950s British aircraft turboshaft engine

The Napier Gazelle is a turboshaft helicopter engine that was manufactured by D. Napier & Son in the mid-1950s. In 1961 production was nominally transferred to a joint venture with Rolls-Royce called Napier Aero Engines Limited. But the venture closed two years later.

<span class="mw-page-title-main">Bristol Orion</span> 1950s British turboprop aircraft engine

The Bristol Orion aero engine is a two-shaft turboprop intended for use in later marks of the Bristol Britannia and the Canadair CL-44. Although the engine was built and underwent a development program, the BE.25 Orion project was cancelled in 1958 by the British Ministry of Supply in favour of the Rolls-Royce Tyne. In addition, interest in turboprop-powered aircraft was beginning to wane, because of the successful introduction of the Boeing 707 and Douglas DC-8 jetliners into airline service.

<span class="mw-page-title-main">Rolls-Royce Gnome</span> 1950s British turboshaft aircraft engine

The Rolls-Royce Gnome is a British turboshaft engine originally developed by the de Havilland Engine Company as a licence-built General Electric T58, an American mid-1950s design. The Gnome came to Rolls-Royce after their takeover of Bristol Siddeley in 1966, Bristol having absorbed de Havilland Engines Limited in 1961.

<span class="mw-page-title-main">Bristol Siddeley Nimbus</span> 1950s British turboshaft aircraft engine

The Bristol Siddeley Nimbus, later known as the Rolls-Royce Nimbus, was a British turboshaft engine developed under license by Blackburn Aircraft Ltd. from the Turbomeca Turmo in the late 1950s. It was used on the Westland Scout and Westland Wasp helicopters.

<span class="mw-page-title-main">Allison Model 250</span> Turboshaft aircraft engine

The Allison Model 250, now known as the Rolls-Royce M250, is a highly successful turboshaft engine family, originally developed by the Allison Engine Company in the early 1960s. The Model 250 has been produced by Rolls-Royce since it acquired Allison in 1995.

<span class="mw-page-title-main">Rolls-Royce RR300</span> Turbine aircraft engine

The Rolls-Royce RR300 is a turbine aircraft engine (turboshaft/turboprop) developed for the light helicopter/general aviation market. Rated at up to 300 shp (224 kW) at take-off power, the RR300 is a rebadged and downrated variant of the Rolls-Royce Model 250-C20.

<span class="mw-page-title-main">Turbomeca Astazou</span>

The Turbomeca Astazou is a highly successful series of turboprop and turboshaft engines, first run in 1957. The original version weighed 110 kg (243 lb) and developed 240 kW (320 shp) at 40,000 rpm. It was admitted for aviation service on May 29, 1961, after a 150-hour test run. The main developing engineer was G. Sporer. It was named after two summits of the Pyrenees.

<span class="mw-page-title-main">Turbomeca Arriel</span> French turboshaft engine

The Turbomeca Arriel is a series of French turboshaft engines that first ran in 1974. Delivering 650 to 1,000 hp, over 12,000 Arriel engines have been produced from 1978 to 2018, logging more than 50 million flight hours for 40 helicopter applications. In June 2018, 1,000 Arriel 2D were in service, powering H125 and H130 single-engine helicopters, having logged one million flight hours since 2011. After endurance tests and fleet data analysis, their TBO increased by 25% to 5,000 hours and mandatory inspection rose to 15 years with no hourly limit, lowering maintenance costs.

<span class="mw-page-title-main">Turbomeca Artouste</span> Early French turboshaft engine

The Turbomeca Artouste is an early French turboshaft engine, first run in 1947. Originally conceived as an auxiliary power unit (APU), it was soon adapted to aircraft propulsion, and found a niche as a powerplant for turboshaft-driven helicopters in the 1950s. Artoustes were licence-built by Bristol Siddeley in the UK, Hindustan Aeronautics Limited in India, and developed by Continental CAE in the US as the Continental T51. Two major versions of the Artouste were produced. The Artouste II family, mainly used in the Aérospatiale Alouette II helicopter, had a one-stage centrifugal compressor and a two-stage turbine, with gearbox-limited power of 300 kW (400 hp). The Artouste III family, mainly used in Aérospatiale's Alouette III and Lama helicopters, had a two-stage axial-centrifugal compressor and a three-stage turbine, with gearbox-limited power of 420–440 kW (560–590 hp).

<span class="mw-page-title-main">Turbomeca Turmo</span>

The Turbomeca Turmo is a family of French turboshaft engines manufacturered for helicopter use. Developed from the earlier Turbomeca Artouste, later versions delivered up to 1,300 kW (1,700 shp). A turboprop version was developed for use with the Bréguet 941 transport aircraft.

<span class="mw-page-title-main">Turbomeca Makila</span>

The Turbomeca Makila is a family of French turboshaft engines for helicopter use, first run in 1976 and flown in 1977.

<span class="mw-page-title-main">General Electric T64</span> Turboshaft engine

The General Electric T64 is a free-turbine turboshaft engine that was originally developed for use on helicopters, but which was later used on fixed-wing aircraft as well. General Electric introduced the engine in 1964. The original engine design included technical innovations such as corrosion resistant and high-temperature coatings. The engine features a high overall pressure ratio, yielding a low specific fuel consumption for its time. Although the compressor is all-axial, like the earlier General Electric T58, the power turbine shaft is coaxial with the HP shaft and delivers power to the front of the engine, not rearwards. Fourteen compressor stages are required to deliver the required overall pressure ratio. Compressor handling is facilitated by 4 rows of variable stators. Unlike the T58, the power turbine has 2 stages.

<span class="mw-page-title-main">Free-turbine turboshaft</span>

A free-turbine turboshaft is a form of turboshaft or turboprop gas turbine engine where the power is extracted from the exhaust stream of a gas turbine by an independent turbine, downstream of the gas turbine. The power turbine is not mechanically connected to the turbines that drive the compressors, hence the term "free", referring to the independence of the power output shaft. This is opposed to the power being extracted from the turbine/compressor shaft via a gearbox.

References

Notes

  1. Gunston 1989, p. 155.
  2. Rolls-Royce Gem product page
  3. Rolls-Royce Gem 42 factsheet Archived 17 December 2010 at the Wayback Machine www.rolls-royce.com. Retrieved: 16 July 2009

Bibliography

  • Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN   1-85260-163-9