Rolls-Royce BR700

The Rolls-Royce BR700 is a family of turbofan engines for regional jets and corporate jets. It is manufactured in Dahlewitz, Germany, by Rolls-Royce Deutschland: this was initially a joint venture of BMW and Rolls-Royce plc established in 1990 to develop this engine. The BR710 first ran in 1995. The United States military designation for the BR725 variant is F130.

Design and development

BR710

The BR710 is a twin shaft turbofan, and entered service on the Gulfstream V in 1997 and the Bombardier Global Express in 1998. This version has also been selected to power the Gulfstream G550.

The BR710 comprises a 48 in (120 cm) diameter single-stage fan, driven by a two-stage LP turbine, and a ten-stage HP compressor (scaled from the V2500 unit) driven by a two-stage, air-cooled, HP turbine.

This engine has a thrust-specific fuel consumption (TSFC) of 0.39 lb/(lbf⋅h) (11 g/(kN⋅s)) at static sea level takeoff and 0.64 lb/(lbf⋅h) (18 g/(kN⋅s)) at a cruise speed of Mach 0.8 and altitude of 35,000 ft (10,668 m).

In May 2017, the 3,200 engines in service reached 10 million flying hours.

Another rerated version, with a revised exhaust system, was selected for the now-cancelled Royal Air Force Nimrod MRA4s.

BR715

The BR715 is another twin-shaft turbofan; this engine was first run in April 1997 and entered service in mid-1999. This version powers the Boeing 717.

A new LP spool, comprising a 58 in (150 cm) diameter single-stage fan, with two-stage LP compressor driven by a three-stage LP turbine, is incorporated into the BR715. The HP spool is similar to that of the BR710.

The IP compressor booster stages supercharge the core, increasing core power and thereby net thrust. However, a larger fan is required, to keep the specific thrust low enough to satisfy jet noise considerations.

This engine has a TSFC of 0.37 lb/(lbf⋅h) (10 g/(kN⋅s)) at static sea level takeoff and 0.62 lb/(lbf⋅h) (18 g/(kN⋅s)) at a cruise speed of Mach 0.8 and altitude of 35,000 ft (10,668 m).^: 96

BR725

The BR725 is a variant of the BR710 to power the Gulfstream G650. Its prototype underwent component bench and its first full engine run in spring 2008. European certification was achieved in June 2009. The first Gulfstream G650, with BR725 engines, was delivered in December 2011.

The engine has a maximum thrust of 16,900 lbf (75.2 kN). The 50 in (130 cm) fan with 24 swept blades is 2 in (5.1 cm) larger than the BR710. The HP axial compressor benefits from three-dimensional aerodynamics for greater efficiency and has 10 stages including five blisks to reduce weight. The BR715 inspired combustor yields a longer life and lower emissions: 80% lower smoke and unburned hydrocarbons and 35% lower NOx than CAEP 6 limits. The two-stage HP turbine has blade active tip-clearance control for more efficiency; 3D aerodynamics reduce the cooling air flow. The LP turbine has three stages instead of two. The BR725 has a bypass ratio of 4.2:1 and is 4 dB quieter than the predecessor BR710. Its cruise thrust specific fuel consumption at Mach 0.85 and FL450 is 0.657 lb/(lbf⋅h) (18.6 g/(kN⋅s)).

F130

On 24 September 2021 the United States Air Force (USAF) selected the F130 (the US military designation for the BR725) for the B-52H Stratofortress Commercial Engine Replacement Program (CERP). This version has 17,000 lbf (75.6 kN) thrust. The USAF will purchase 650 engines (608 direct replacements, 42 spare engines) for its fleet of 76 B-52H aircraft in a $2.6 billion deal. Upgraded aircraft will be will be redesignated as B-52Js. The CERP engines will be built at Rolls-Royce North America's Indianapolis, Indiana, plant.

Future developments

The Advance 2 development effort inserts new, advanced technology into existing 15,000 lbf (67 kN) class BR710 and the larger BR725 engines. An even larger engine will also be made, with a 52 in (130 cm) fan. The BR710 and BR715 main developments, the next generation of 44–89 kN (10,000–20,000 lbf) engines to be introduced in the 2020s, will have an Advance 3 core, improved engine health management, newer materials, and cooling. They will also have a “blisk” fan made out of titanium, with an overall pressure ratio of 50:1. These improvements will yield a 10% thrust specific fuel consumption reduction, 50% NOx margin improvement, 99.995% reliability, and a 20% better thrust-to-weight ratio.

Pearl 15

The Pearl engine was developed in Dahlewitz from the BR700 with Advance2 technologies. EASA certification was applied for on 28 February 2015. It made its first ground run in 2015, type tests in 2016, and flight tests in 2017. Six test engines logged over 6,000 cycles on 2,000 test hours. The test program included lightning strike, water ingestion, ice, and -40 °C cold-start testing.

EASA certification was granted on 28 February 2018 and it was unveiled on 28 May 2018. It was undergoing flight tests in May 2018 for an end of 2019 planned entry into service aboard the Bombardier Global Express 5500 and 6500 developments. It should have logged 10,000 hours by then.

Its layout is similar to the BR725, with the same stage count and 24 titanium fan blades. Its fan has a 48.5 in (123 cm) diameter. The enhanced 3-stage LP turbine with advanced high temperature materials, advanced segments and seals allow for higher pressures and temperatures and the new low emissions cooled combustor includes a new tiled combustion chamber. Its core uses advanced nickel alloys and ceramic coatings, includes a new 10-stage HP compressor with 6 titanium blisks and a new 2-stage HP turbine with enhanced aerodynamics and blade cooling, enhanced segments and seals.

Its overall pressure ratio attains 43:1 and its bypass ratio 4.8:1. The HP compressor ratio rises to 24:1. It delivers up to 9% more thrust with 15,125 lbf (67.28 kN) and a 7% TSFC improvement while being 2 decibels quieter. Health monitoring should improve on the BR710 99.97% dispatch reliability which is logging one unplanned engine removal per 100,000 hours while the BR715 is approaching zero unplanned removals.

Pearl 700

The Pearl 700 will power the Gulfstream G700, a stretch of the previous G650, and the G800, with more range than the G650ER. Evolved from the BR725 with a similar architecture plus a fourth low-pressure turbine stage and a 2 in (5.1 cm) larger, 51.8 in (132 cm) blisk fan, its bypass ratio is higher than 6.5:1 and its overall pressure ratio should exceed 50:1. It should provide 18,250 lbf (81.2 kN) of thrust, 3-5% better thrust specific fuel consumption than the BR725 variant powering the Gulfstream G650, reduced emissions and lower noise.

Pearl 10X

The upcoming Dassault Falcon 10X will be powered by two Pearl 10X engines over 18,000 lbf (80 kN) thrust, with a titanium fan blisk, a 10-stage HP compressor, a two-stage shroudless HP turbine and a four-stage LP turbine. The initial Pearl 10X test engine was first run in early 2022 and the programme had accumulated 1,000h of testing by May, along with the Advance2 demonstrator. The Advance2 core and new low-pressure system allows 5% more efficiency than the previous Rolls-Royce business jet engines.

Variants

BR700-710A1-10

Variant with a 14,700 lbf (65.6 kN) takeoff rating and a maximum diameter of 72 in (1,820 mm) for the Gulfstream GV.

BR700-710A2-20

Variant with a 14,700 lbf (65.6 kN) takeoff rating and a maximum diameter of 72 in (1,820 mm) for the Bombardier Global Express/XRS/5000/6000.

BR700-710B3-40

Variant with a 16,000 lbf (69 kN) takeoff rating for the BAE Systems Nimrod MRA4.

BR700-710C4-11

Variant with a 15,400 lbf (68.4 kN) takeoff rating and a maximum diameter of 70.3 in (1,785 mm) for the Gulfstream GV-SP (G500/G550).

BR700-710D5-21

Variant with a 15,200 lbf (67.8 kN) takeoff rating and a maximum radius of 39 in (980 mm) for the Bombardier Global 5500/6500.

BR700-715A1-30

Variant with a 18,710 lbf (83.23 kN) takeoff rating for Boeing 717-200 basic gross weight variants.

BR700-715B1-30

Variant with an 20,160 lbf (89.68 kN) takeoff rating.

BR700-715C1-30

Variant with a 21,430 lbf (95.33 kN) takeoff rating for Boeing 717-200 high gross weight variants.

BR700-725A1-12

Variant with a 16,900 lbf (75.2 kN) takeoff rating and a fan diameter of 50 in (1,270 mm) for the Gulfstream GVI (G650).

F130

Military variant of the BR700-725 with a 17,000 lbf (75.62 kN) maximum rating for the Boeing B-52 Stratofortress.

BR700-TP

Turboprop variant rated at 7,460 kilowatts (10,000 shaft horsepower) and proposed for the European Future Large Aircraft (which became the Airbus A400M Atlas military transporter/tanker).

The BR715 thrust ratings can be adjusted by changing a plug in the FADEC controller, meaning no engine change is required. The A1-30 can become a C1-30 with a simple plug and software change.

Applications

• BAE Systems Nimrod MRA4
• Bombardier Global Express
• Boeing 717
• Boeing B-52J Stratofortress (F130 variant)
• Dassault Falcon 10X
• Gulfstream V
• Gulfstream G550
• Gulfstream G650/G700
• Rekkof/Fokker XF70/XF100
• Tupolev Tu-334

Specifications

See also

Comparable engines

• General Electric CF34
• General Electric Passport
• IAE V2500
• PowerJet SaM146
• Pratt & Whitney PW6000
• Pratt & Whitney Canada PW800
• Progress D-436

Related lists

• List of aircraft engines

References

External links

• BR700: Technical data
• BR710: Power for ultra-long range business jets and special mission aircraft
• Guy Norris (2 June 1999). "European powerhouse". Flight International.