The Turbo-Union RB199 is a
turbofan
The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which ac ...
jet engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term ...
designed and built in the early 1970s by
Turbo-Union
Turbo-Union Limited is a joint venture between three European aero-engine manufacturers, FiatAvio (now Avio), MTU Aero Engines and Rolls-Royce.
Products
The company's only product is the RB199, a three-spool turbofan developed specifically for ...
, a joint venture between
Rolls-Royce
Rolls-Royce (always hyphenated) may refer to:
* Rolls-Royce Limited, a British manufacturer of cars and later aero engines, founded in 1906, now defunct
Automobiles
* Rolls-Royce Motor Cars, the current car manufacturing company incorporated in ...
,
MTU and
Aeritalia
Aeritalia was an aerospace engineering corporation based in Italy. It was formed out of the merger of two aviation companies, Fiat Aviazione and Aerfer, in 1969.
Aeritalia continued several programs of its preceding companies, perhaps most p ...
. The only production application was the
Panavia Tornado
The Panavia Tornado is a family of twin-engine, variable-sweep wing multirole combat aircraft, jointly developed and manufactured by Italy, the United Kingdom and West Germany. There are three primary Tornado variants: the Tornado IDS (inter ...
.
Design and development
![Turbo Union RB199 Montrose](https://upload.wikimedia.org/wikipedia/commons/1/1f/Turbo_Union_RB199_Montrose.jpg)
The RB199 originated with a requirement, in 1969, to power a new European
multirole combat aircraft
A multirole combat aircraft (MRCA) is a combat aircraft intended to perform different roles in combat. These roles can include air to air combat, air support,
aerial bombing, reconnaissance, electronic warfare, and suppression of air defens ...
(MRCA) called the
Panavia MRCA. The engine requirements to meet the Panavia MRCA specification were significant advances over current engines in thrust-to-weight ratio, fuel consumption and size. The final selection of the engine for the MRCA was made between a new European collaboration,
Turbo Union
Turbo-Union Limited is a joint venture between three European aero-engine manufacturers, FiatAvio (now Avio), MTU Aero Engines and Rolls-Royce.
Products
The company's only product is the RB199, a three-spool turbofan developed specifically for ...
, with the RB199, and Pratt & Whitney who proposed the JTF16. The Panavia MRCA would later be called the
Panavia Tornado
The Panavia Tornado is a family of twin-engine, variable-sweep wing multirole combat aircraft, jointly developed and manufactured by Italy, the United Kingdom and West Germany. There are three primary Tornado variants: the Tornado IDS (inter ...
.
Advanced engine studies at
Bristol Siddeley
Bristol Siddeley Engines Ltd (BSEL) was a British aero engine manufacturer. The company was formed in 1959 by a merger of Bristol Aero-Engines Limited and Armstrong Siddeley Motors Limited. In 1961 the company was expanded by the purchase of t ...
had already been done to support the
BAC/Dassault AFVG and were based on the Pegasus two-spool arrangement. At
Rolls-Royce
Rolls-Royce (always hyphenated) may refer to:
* Rolls-Royce Limited, a British manufacturer of cars and later aero engines, founded in 1906, now defunct
Automobiles
* Rolls-Royce Motor Cars, the current car manufacturing company incorporated in ...
, where the three spool RB211 engine was in development, 3 shafts were considered better. Rolls-Royce took over Bristol Siddeley in 1967 so the configuration for the RB199 was decided jointly, a three shaft engine.
The overall design concept for the international collaborative program, 3 shafts and a
bypass ratio
The bypass ratio (BPR) of a turbofan engine is the ratio between the mass flow rate of the bypass stream to the mass flow rate entering the core. A 10:1 bypass ratio, for example, means that 10 kg of air passes through the bypass duct for ev ...
(BPR) of about 1.2, was decided by Rolls-Royce. The bypass ratio was chosen for long-range, low fuel consumption particularly when throttled back. The selected BPR also gave a higher reheat boost than with smaller values used on similar engines such as 0.4. The design of the individual modules was shared between Rolls-Royce, MTU and Fiat according to their existing expertise. For example, Rolls-Royce designed the fan using scaled-down Pegasus knowledge. They also did the combustor, high pressure (HP) turbine and
reheat
An afterburner (or reheat in British English) is an additional combustion component used on some jet engines, mostly those on military supersonic aircraft. Its purpose is to increase thrust, usually for supersonic flight, takeoff, and combat ...
. The reheat used cold air combustion techniques, described by Sotheran and which were derived from their experience with ramjets and plenum chamber burning (PCB) in Pegasus front nozzles. Fiat had built turbines for the Viper so did the low pressure(LP) turbine as well as the final nozzle. MTU did the intermediate pressure(IP) and high pressure (HP) compressor, IP turbine and thrust reverser.
A three-spool arrangement reduces the pressure ratio on each compressor so no variable stators were needed. To meet the short afterburner requirement an arrangement known as mix-then-burn, as used in current engines, was not possible because it was too long and heavy. The RB199 used a much shorter arrangement known as mix/burn.
The first test run of the RB199 was done on 27 September 1971 at Patchway, UK. It was flight-tested using an
Avro Vulcan
The Avro Vulcan (later Hawker Siddeley Vulcan from July 1963) is a jet-powered, tailless, delta-wing, high-altitude, strategic bomber, which was operated by the Royal Air Force (RAF) from 1956 until 1984. Aircraft manufacturer A.V. Roe and ...
with the engine installed in a
nacelle
A nacelle ( ) is a "streamlined body, sized according to what it contains", such as an engine, fuel, or equipment on an aircraft. When attached by a pylon entirely outside the airframe, it is sometimes called a pod, in which case it is attached ...
that was representative of the Tornado aircraft. The Vulcan first flew with the RB199 in 1972.
Service flying with the Royal Air Force, German Navy and German and Italian Air Forces in the European environment showed normal failure mechanisms for turbine blades,
thermal fatigue Thermo-mechanical fatigue (short TMF) is the overlay of a cyclical mechanical loading, that leads to fatigue of a material, with a cyclical thermal loading. Thermo-mechanical fatigue is an important point that needs to be considered, when construct ...
,
creep and high cycle fatigue (
HCF) so development started on replacing the initial production equiaxed blades with single-crystal ones which last longer at high temperatures.
Sand ingestion tests had been done and passed as part of the qualification for service introduction but operating in desert conditions with the
Royal Saudi Air Force
The Royal Saudi Air Force ( ar, الْقُوَّاتُ الْجَوِّيَّةُ الْمَلَكِيَّةْ ٱلسُّعُوْدِيَّة, Al-Quwwat Al-Jawiyah Al-Malakiyah as-Su’udiyah) (RSAF) is the aviation branch of the Saudi Arabia ...
produced new problems. Frequent flying in air carrying different sizes of sand particles caused deposits on the HP turbine blades from sand passing through the combustor. In addition, sand carried with the cooling air through the blades blocked the cooling holes. Single crystal blades were being introduced to improve the life of the blades for the European operating conditions and revised cooling hole arrangements were introduced at the same time to reduce the detrimental effect of sand on blade cooling. With incorporation of these blade processing and cooling changes "Desert Storm Tornado aircraft flew some of the most arduous missions of any Allied aircraft with reliability no worse than peacetime and no engines were rejected for HP Turbine blade defects."
Looking back on the RB199 program in 2002 Chief Engineer for the RB199, Dr.Gordon Lewis, concluded "The final production standard provided satisfactory reliability and performance."
[The Birth Of Tornado, Royal Air Force Historical Society 2002, , RB199- The Engine For Tornado by Dr. Gordon Lewis, p.50]
Variants and applications
;RB199 Mk 101
:Initial variant powered first Tornado IDS deliveries, with a 38.7kN (8700lbf) dry thrust, 66.01kN (14840lbf) with afterburner.
[Taylor 1996, pp. 610–611]
;RB199 Mk 103
:Powering
Tornado IDS
The Panavia Tornado is a family of Twinjet, twin-engine, variable-sweep wing multirole combat aircraft, jointly developed and manufactured by Italy, the United Kingdom and West Germany. There are three primary #Variants, Tornado variants: the ...
strike versions, with a thrust rating of 40.5
kN (dry) 71.2 kN
(reheat)
;RB199 Mk 104
:Powering the
Tornado F3 Air Defence Variant, with a thrust rating of 40.5 kN (dry) 73 kN (reheat)
;RB 199 Mk104D
:Derivative used on the
BAe EAP
The British Aerospace EAP (standing for ''Experimental Aircraft Programme'') was a British technology demonstrator aircraft developed by aviation company British Aerospace (BAe) as a private venture. It was designed to research technologies to ...
.
;RB199 Mk 105
:Powering
Tornado ECR
The Panavia Tornado is a family of twin-engine, variable-sweep wing multirole combat aircraft, jointly developed and manufactured by Italy, the United Kingdom and West Germany. There are three primary Tornado variants: the Tornado IDS (inter ...
versions and applicable to IDS, with a thrust rating of 42.5 kN (dry) 74.3 kN (reheat)
;RB199-122
:A derivative of the Mk104 (originally designated Mk 104E
), powering the first two prototypes of the
Eurofighter Typhoon
The Eurofighter Typhoon is a European multinational twin-engine, canard delta wing, multirole fighter. The Typhoon was designed originally as an air-superiority fighter and is manufactured by a consortium of Airbus, BAE Systems and Leonardo ...
(DA1 and DA2) until the initial versions of the
Eurojet EJ200
The Eurojet EJ200 is a military low-bypass turbofan used as the powerplant of the Eurofighter Typhoon. The engine is largely based on the Rolls-Royce XG-40 technology demonstrator, which was developed in the 1980s. The EJ200 is built by the ...
were available.
Engines on display
A Turbo-Union RB199 is on public display at the
Royal Air Force Museum Cosford
The Royal Air Force Museum Cosford, located in Cosford in Shropshire, is a free (currently, 2022) museum dedicated to the history of aviation and the Royal Air Force in particular. The museum is part of the Royal Air Force Museum, a non-departme ...
and
Brooklands Museum Weybridge.
A Turbo-Union RB199 is on public display at the Morayvia Centre in Kinloss.
A Turbo-Union RB199 is on public display at the
Montrose Air Station Heritage Centre
The Montrose Air Station Heritage Centre is located to the North of Montrose, Angus, Scotland. Montrose has the distinction of having the first operational military airfield in Great Britain and the Heritage Centre is located on the former ...
Specifications (RB199-104)
See also
References
;Notes
;Bibliography
*
External links
Rolls-Royce.com - RB199
{{DEFAULTSORT:Turbo-Union Rb199
Low-bypass turbofan engines
1970s turbofan engines
Three-spool turbofan engines