F119 and F135?

All about the Pratt & Whitney F135 and the (cancelled) General Electric/Rolls-Royce F136
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Corsair1963

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Unread post24 May 2010, 11:19

How closely related are the P & W F119 and P & W F135?
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Unread post24 May 2010, 13:40

The F135 is a direct evolution of the F119 and much of the JSF's maintainability improvements extend directly from it:

From GlobalSecurity (~2006)

The F119 has 40 percent fewer major parts than current fighter engines, and each part is more durable and does its job more efficiently. Computational fluid dynamics (CFD), the study of airflow using advanced computers, led to the design of engine turbomachinery of unprecedented efficiency, giving the F119 more thrust with fewer turbine stages.

The F119 cuts requirements for support equipment and labor by one-half, which also saves precious space in airlifters in combat zone deployments. The F119 will require 75 percent fewer shop visits for routine maintenance than its predecessors.

Features
• Integrally bladed rotors: In most stages, disks and blades are made from a single piece of metal for better performance and less air leakage.
• Long chord, shroudless fan blades: Wider, stronger fan blades eliminate the need for the shroud, a ring of metal around most jet engine fans. Both the wider blades and shroudless design contribute to engine efficiency.
• Low-aspect, high-stage-load compressor blades: Once again, wider blades offer greater strength and efficiency.
• Alloy C high-strength burn-resistant titanium compressor stators: Pratt & Whitney's innovative titanium alloy increases stator durability, allowing the engine to run hotter and faster for greater thrust and efficiency.
• Alloy C in augmentor and nozzle: The same heat-resistant titanium alloy protects aft components, permitting greater thrust and durability.
• Floatwall combustor: Thermally isolated panels of oxidation-resistant high cobalt material make the combustion chamber more durable, which helps reduce scheduled maintenance.
• Fourth-generation full-authority digital electronic engine control (FADEC): Dual-redundant digital engine controls - two units per engine, two computers per unit - ensure unmatched reliability in engine control systems. The same experience that introduced full-authority digital control to fighter engines works with the aircraft system to make engine and aircraft function as a single flight unit.
• No visible smoke: Reduces the possibility of an enemy visually detecting the F-22.
• Improved Supportability: All components, harnesses, and plumbing are located on the bottom of the engine for easy access, all line replaceable units (LRUs) are located one deep (units are not located on top of one another), and each LRU can be removed with just one of the six standard tools required for engine maintenance.

http://www.globalsecurity.org/military/systems/aircraft/f-22-f119.htm
http://www.globalsecurity.org/military/systems/aircraft/systems/f135.htm
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Unread post25 May 2010, 03:05

jeffb wrote:
Corsair1963 wrote:How closely related are the P & W F119 and P & W F135??? :?:


The F135 is a direct evolution of the F119 and much of the JSF's maintainability improvements extend directly from it:

From GlobalSecurity (~2006)

The F119 has 40 percent fewer major parts than current fighter engines, and each part is more durable and does its job more efficiently. Computational fluid dynamics (CFD), the study of airflow using advanced computers, led to the design of engine turbomachinery of unprecedented efficiency, giving the F119 more thrust with fewer turbine stages.

The F119 cuts requirements for support equipment and labor by one-half, which also saves precious space in airlifters in combat zone deployments. The F119 will require 75 percent fewer shop visits for routine maintenance than its predecessors.

Features
• Integrally bladed rotors: In most stages, disks and blades are made from a single piece of metal for better performance and less air leakage.
• Long chord, shroudless fan blades: Wider, stronger fan blades eliminate the need for the shroud, a ring of metal around most jet engine fans. Both the wider blades and shroudless design contribute to engine efficiency.
• Low-aspect, high-stage-load compressor blades: Once again, wider blades offer greater strength and efficiency.
• Alloy C high-strength burn-resistant titanium compressor stators: Pratt & Whitney's innovative titanium alloy increases stator durability, allowing the engine to run hotter and faster for greater thrust and efficiency.
• Alloy C in augmentor and nozzle: The same heat-resistant titanium alloy protects aft components, permitting greater thrust and durability.
• Floatwall combustor: Thermally isolated panels of oxidation-resistant high cobalt material make the combustion chamber more durable, which helps reduce scheduled maintenance.
• Fourth-generation full-authority digital electronic engine control (FADEC): Dual-redundant digital engine controls - two units per engine, two computers per unit - ensure unmatched reliability in engine control systems. The same experience that introduced full-authority digital control to fighter engines works with the aircraft system to make engine and aircraft function as a single flight unit.
• No visible smoke: Reduces the possibility of an enemy visually detecting the F-22.
• Improved Supportability: All components, harnesses, and plumbing are located on the bottom of the engine for easy access, all line replaceable units (LRUs) are located one deep (units are not located on top of one another), and each LRU can be removed with just one of the six standard tools required for engine maintenance.

http://www.globalsecurity.org/military/systems/aircraft/f-22-f119.htm
http://www.globalsecurity.org/military/systems/aircraft/systems/f135.htm



How does that relate to the F135??? Plus, do they share any parts whatsoever???
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Unread post25 May 2010, 04:32

Corsair1963 wrote:
jeffb wrote:
Corsair1963 wrote:How closely related are the P & W F119 and P & W F135??? :?:


The F135 is a direct evolution of the F119 and much of the JSF's maintainability improvements extend directly from it:

From GlobalSecurity (~2006)

The F119 has 40 percent fewer major parts than current fighter engines, and each part is more durable and does its job more efficiently. Computational fluid dynamics (CFD), the study of airflow using advanced computers, led to the design of engine turbomachinery of unprecedented efficiency, giving the F119 more thrust with fewer turbine stages.

The F119 cuts requirements for support equipment and labor by one-half, which also saves precious space in airlifters in combat zone deployments. The F119 will require 75 percent fewer shop visits for routine maintenance than its predecessors.

Features
• Integrally bladed rotors: In most stages, disks and blades are made from a single piece of metal for better performance and less air leakage.
• Long chord, shroudless fan blades: Wider, stronger fan blades eliminate the need for the shroud, a ring of metal around most jet engine fans. Both the wider blades and shroudless design contribute to engine efficiency.
• Low-aspect, high-stage-load compressor blades: Once again, wider blades offer greater strength and efficiency.
• Alloy C high-strength burn-resistant titanium compressor stators: Pratt & Whitney's innovative titanium alloy increases stator durability, allowing the engine to run hotter and faster for greater thrust and efficiency.
• Alloy C in augmentor and nozzle: The same heat-resistant titanium alloy protects aft components, permitting greater thrust and durability.
• Floatwall combustor: Thermally isolated panels of oxidation-resistant high cobalt material make the combustion chamber more durable, which helps reduce scheduled maintenance.
• Fourth-generation full-authority digital electronic engine control (FADEC): Dual-redundant digital engine controls - two units per engine, two computers per unit - ensure unmatched reliability in engine control systems. The same experience that introduced full-authority digital control to fighter engines works with the aircraft system to make engine and aircraft function as a single flight unit.
• No visible smoke: Reduces the possibility of an enemy visually detecting the F-22.
• Improved Supportability: All components, harnesses, and plumbing are located on the bottom of the engine for easy access, all line replaceable units (LRUs) are located one deep (units are not located on top of one another), and each LRU can be removed with just one of the six standard tools required for engine maintenance.

http://www.globalsecurity.org/military/systems/aircraft/f-22-f119.htm
http://www.globalsecurity.org/military/systems/aircraft/systems/f135.htm



How does that relate to the F135??? Plus, do they share any parts whatsoever???


Sigh. "Evolution" in this context means "came from" or "based upon", so the F135 is based on the F119. From http://www.f135engine.com/proven-tech/common-core.shtml

The technologically advanced F135 engine is an evolution of the highly successful Pratt & Whitney F119, power for the F-22 Raptor. The F119 engine is the only fifth generation fighter currently in operation, making Pratt & Whitney the leader in next generation fighter propulsion.

The F135 improves upon the validated F119 core, integrating the F119's high-performance six-stage compressor and single-stage turbine unit with a new low-pressure spool. Together the F135 and F119 will have logged more than 600,000 flight hours before the F-35's introduction into operational service in 2012.


So, the F135 is basically a F119 modified to produce more thrust (~35000lbs to ~43000lbs) apparently at the cost of not being able to supercruise (according to several sources I've seen).

If you need more detail than that you might ask That Engine Guy or LMAggie if they've got more details.
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Unread post25 May 2010, 05:24

Actually, I was hoping TEG would jump in........
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Unread post25 May 2010, 13:38

jeffb wrote:
So, the F135 is basically a F119 modified to produce more thrust (~35000lbs to ~43000lbs) apparently at the cost of not being able to supercruise (according to several sources I've seen).

If you need more detail than that you might ask That Engine Guy or LMAggie if they've got more details.


Actually the F-119 is more in the 37-39k lb thrust range, and as far as the F-135 being able to supercruise- the key thing to bear in mind is the threshold used to define supercruise. Not being able to cruise at M1.5 or greater doesn't necessarily mean unable to cruise at >M1.
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Unread post25 May 2010, 17:44

Larger fan (Higher flow and pressure)
Larger dual stage low pressure turbine to drive the larger fan, and LiftFan when equipped)
Advanced prognostics (fancy computers that monitor performance based on predicted and modeled goals)
Newer Externals

Most of it is 'based on' the F119; but it won't be the 'same'. The core is 'based on the F119' but will incorporate improvements learned over the F119's operational history. The F135 is also suppose to have a reduced part count; lower than the F119, which is much lower than the F100 or F110.

Even the Fan and low pressure turbine are 'based' on the F119; improved and enlarged.

I'll pop over to visit our friend J@ne and see the technical explanation of the above changes.

And yes, the F119 is 'rated' in the "35K class" which may or may not be accurate depending on how you look at it.... :cool:

The F135's 43K figure has been stated by the F-35 office, PW, and the DoD. It too is in the '40K class' (So take the classes or actual as you will.)

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Unread post25 May 2010, 23:59

wrightwing wrote:
jeffb wrote:
So, the F135 is basically a F119 modified to produce more thrust (~35000lbs to ~43000lbs) apparently at the cost of not being able to supercruise (according to several sources I've seen).

If you need more detail than that you might ask That Engine Guy or LMAggie if they've got more details.


Actually the F-119 is more in the 37-39k lb thrust range, and as far as the F-135 being able to supercruise- the key thing to bear in mind is the threshold used to define supercruise. Not being able to cruise at M1.5 or greater doesn't necessarily mean unable to cruise at >M1.


It may be splitting hairs but I think it's the ability to efficiently cruise at >M1. The 43klbs output of the F135 can push the F-35 to more than M1 at certain altitudes without going to burner but can it cruise efficiently at those speeds? The F119 was specifically designed to allow the aircraft to cruise at M1.5+, to work in that flight regime, the F135 was not. The bigger fan and turbine stages are the compromises made to increase the amount of air that gets pushed through the engine and increase the thrust correspondingly. To keep that all working effectively at high mach for sustained periods is another matter.
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Unread post26 May 2010, 01:21

jeffb seems to complain (but maybe he isn't and I'm not having a 'go' at him) just sayin' : ".... apparently at the cost of not being able to supercruise (according to several sources I've seen)."

A New Fighter Paradigm by C.A. Robinson quoting RADM Steven Enewold page 25 in 'Faircount_-_F-35_Lightning_II.pdf' (http://www.zshare.net/download/765117503fa3c3df/) [53Mb]

"Capable of supersonic dash speeds, the F-35 is not designed for supersonic cruise capability, Enewold said."
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Unread post26 May 2010, 01:39

Probably repeating what has been said but here is another source from same PDF mentioned above.
Attachments
EvolutionJSFengine.gif
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Unread post26 May 2010, 03:37

spazsinbad wrote:jeffb seems to complain (but maybe he isn't and I'm not having a 'go' at him) just sayin' : ".... apparently at the cost of not being able to supercruise (according to several sources I've seen)."

A New Fighter Paradigm by C.A. Robinson quoting RADM Steven Enewold page 25 in 'Faircount_-_F-35_Lightning_II.pdf' (http://www.zshare.net/download/765117503fa3c3df/) [53Mb]

"Capable of supersonic dash speeds, the F-35 is not designed for supersonic cruise capability, Enewold said."


yah, but is he basing that on engine performance or aerodynamic shape? I've read elsewhere that the F-35 has a wing which is "optimised for transonic maneuver"; would this stop it from efficiently cruising above M1?
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Unread post26 May 2010, 04:36

jeffb, why does it have to be one or tuther? Cannot it be both engine and airframe not designed for such a purpose (supersonic cruise capability)? I have read (and I'm not going to go looking for references) that there were many considerations. Some are contained in the 'Designing JSF for shipboard ops' PDF as I recall. JSF is designed for lots of flight situations and supercruise is not one. Here is one reference that comes to mind:

The Influence of Ship Configuration on the Design of the Joint Strike Fighter: (1Mb PDF)
http://handle.dtic.mil/100.2/ADA399988
"While the implications of shipboard compatibility have long influenced the design of maritime-based aircraft, the Joint Strike Fighter (JSF) is unique in that the program is centered on the concurrent development of a family of highly common aircraft variants, two of which are to operate from distinctly different ship types. This procurement strategy poses a formidable challenge to the aircraft designer: How to design an air system that meets the unique needs of its multiple warfighter customers while preserving enough commonality to reap the benefits of the "family" approach to design, manufacture, and operational sustainment. This paper describes how the configurations of the United States Navy's aircraft carriers and amphibious assault ships, as well as the United Kingdom Royal Navy's INVINCIBLE-class of carriers, have influenced the basic configurations of the catapult launch / arrested landing (CV) and the short takeoff/ vertical landing (STOVL) variants of the JSF. From these discussions, the designers of future air capable ships can better understand which characteristics of current ship designs impose the most significant constraints for the aircraft based aboard them, and where ship/air interface considerations should play."
&
"SHIP SUITABILITY DESIGN "PENALTY" page 10 of 11 (from PDF above)

http://www.dtic.mil/cgi-bin/GetTRDoc? AD=ADA399988&Location=U2&doc=GetTRDoc.pdf

Because of the numerous factors that influence the design of a ship-based aircraft, many assume these
considerations have significantly compromised the mission performance of the CV and STOVL variants. Correspondingly, it is assumed that the remaining CTOL variant carries appreciable "scar impacts" to maintain commonality with its sea-going siblings.

However, the JSF design solution has been quite successful in minimizing the "penalty" of ship suitability....

...the CTOL variant carries virtually no scars as the result of the ship suitability of the other two variants. The JSF program has clearly shown that shipboard compatibility does not have to come at the expense of such critical attributes as lethality and survivability."
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Unread post26 May 2010, 17:45

jeffb wrote:
spazsinbad wrote:jeffb seems to complain (but maybe he isn't and I'm not having a 'go' at him) just sayin' : ".... apparently at the cost of not being able to supercruise (according to several sources I've seen)."

A New Fighter Paradigm by C.A. Robinson quoting RADM Steven Enewold page 25 in 'Faircount_-_F-35_Lightning_II.pdf' (http://www.zshare.net/download/765117503fa3c3df/) [53Mb]

"Capable of supersonic dash speeds, the F-35 is not designed for supersonic cruise capability, Enewold said."


yah, but is he basing that on engine performance or aerodynamic shape? I've read elsewhere that the F-35 has a wing which is "optimised for transonic maneuver"; would this stop it from efficiently cruising above M1?


Neither the F-16 nor F-18 were designed to supercruise either, but when clean, both of them can cruise at >M1 without A/B.
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Unread post27 May 2010, 00:25

So does the F-35 supercruise?
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Unread post27 May 2010, 02:52

Here it is.... Everything you wanted to know (that isn't Cl@$sifieD) about the F135 engine.

From our friend J@nE'$.

Keep 'em flyin' :thumb:
TEG

The JSF-F119 was the engine of the X-35 concept demonstrators, and because of the short time-scale it was in turn a direct derivative of the F-22's F119 engine.

In contrast, the F135 is optimised for the propulsion of the F-35, though it is likewise derived from the F119, and is thus a two-shaft low-BPR turbofan with an augmentor. On the basis of information released by 2005 the only significant difference between the two engines is that the F135 has a two-stage LP turbine (that of the F119 having a single stage). Whereas the F119 is loosely described as being "in the 35,000 lb (155.75 kN) class", and the JSF-F119 as being rated in the 170 kN (38,200 lb) class, the F135 is described as "in the 40,000 lb (178 kN) class." Indeed, it is likely that the F135 will eventually be developed to give power well beyond the figures given in the data below.

Apart from the broad outline given in the description below, because of its high security classification, little is publicly known of the actual hardware of the F135, apart from the overall opinion that, as the crucial blading is all fractionally larger, because of the greater mass flows, the engine should be exceptionally tough and durable. Pratt & Whitney has, however, been permitted to disclose some of the radical advances that this engine will introduce in the fields of self-diagnostics and health monitoring. Among technological "firsts" claimed for the basic F135 are on-wing (this simply means "with the engine installed in the aircraft") trim balancing, elimination of the need to rig the installation on replacing an engine, and the elimination of safety wire (previously used to ensure security of such items as nuts and bolts).

Ground-breaking PHM health-monitoring and self-diagnostics systems. The intention is that PHM, a new acronym which will become important (meaning Prognostics and Health-Monitoring), will automatically take account of any in-flight fault, or incipient fault, adjust engine operation and inform the pilot, and in real time transfer data to the aircraft's home base. Thus, any replacement components will be ready for retrofit as the aircraft lands, with the engine pronounced fit again (the plan is) in about 15 minutes, which is said to be a 94 per cent improvement over present times. Of course, that is based on the replacement of externals, not such items as turbine blades.

Externals, in fact, differ markedly from those of the F119 used in the twin-engined F/A-22, though accessories are grouped on the underside as in the ancestor engine. The F135 is expected to set a new low need for special maintenance tools, and to have every external item immediately available upon opening the large access doors with stealth-type zig-zag edges. Indeed, Pratt & Whitney says "all critical features" will be at once accessible. Objectives include a reduction in operating cost -- presumably compared with such engines as the F100-PW-229, for example -- of 50 per cent, and an extension in time between scheduled maintenance of 225 per cent (one F135 document even claims "Scheduled maintenance requirement eliminated"). To this end, PHM will make use of electrostatic and other sensors to monitor such parameters as debris generation, vibration, blade health and lubricating-oil quality. The suite of sensors will constantly monitor approximately 500 data streams, which will be integrated with the F-35's own systems. The complete PHM system has been developed in partnership with NASA Ames, which created vital data-fusion algorithms, NASA Dryden and NASA Glenn, with flight development to be carried out with a C-17. As noted previously, the aim is to predict the need for inspection or parts-replacement, so that, via a satellite link, the airbase or aircraft carrier knows the engine health before the aircraft returns from its mission.

Apart from the challenging 94 per cent improvement in fault-rectification time, other design objectives include a 35 per cent reduction in cost of ownership, compared to legacy systems, a reduction in fault-detection time despite a 50 per cent reduction in the number of maintenance technicians, three times the hot-section reliability, and a 225 per cent increase in time between shop visits.

Back in 1997 the JSF programme had firmed up into three major aircraft versions, conventional (CTOL), STOVL and carrier (CV). Today these are designated as:

F-35A Engine: F135-PW-100. This is the baseline version of the F135.

F-35B Engine: F135-PW-600. This engine differs from other versions in incorporating a vectoring nozzle, bleed-air ports for roll posts for lateral control at low airspeeds, and a forward drive shaft to the LiftFan to provide lift independently of the wings. The basic engine is identical to other versions.

F-35C Engine: F135-PW-400. This is almost identical to the F135-PW-100, apart from small changes in accessories, and elimination of materials not resistant to salty environments.


The following refers principally to the SDD engines:

Type: Two-shaft augmented turbofan, the F135-PW-600 version having additional STOVL features.

Intake: The intake hub is the same in all versions, being unaffected by connection of the LiftFan drive shaft.

Fan: Three integrally bladed rotors, derived from F119 but with new features giving greater mass flow with higher pressure ratio, improved stability, maximum resistance to bird and other impact damage, and minimum signature. Significantly lighter and less costly than predecessors, yet provides most of the thrust. The casing is the first to be made for the US military from organic-matrix composite (OMC) material. First-stage vanes (stators) hollow OMC, rotors 2 and 3 flank-milled titanium alloy. Split casing permitting reblading or minor repairs, and weld repairs are (mid-2004) being developed for all stages. Inside the nosecone a single bolt permits removal of the fan module in 40 minutes. This bolt is replaced in the Dash-600 engine by a connector to the LiftFan drive shaft. Inlet diameter 1,168 mm (46.0 in). Bypass ratio, (F135-PW-100, -400) 0.57; (F135-PW-600), conventional flight 0.56, powered lift 0.514.

HP Compressor: Six-stage SDD compressor derived from F119, rotating in opposition to LP spool. Split forward case in titanium alloy housing two stages of asymmetric variable-incidence guide vanes (stators). Cast nickel-alloy rear stators grouped in segments in titanium-alloy ring casing of high creep strength. All stators integrally bladed, either flat-milled like the fan or high-speed milled. All six rotors integrally bladed, first two in damage-tolerant titanium alloy, the remainder high-strength nickel alloy. Crucial No 3 bearing is a simple squirrel-cage unit, lighter and easier to install than the corresponding bearing in the F119 (which comprises a ring and 24 rods). The production bearing may be made of corrosion-resistant silicon nitride hybrid ceramic. Mass flow (F135-100) 139.6 kg (307.8 lb)/s. OPR (F135-PW-100, -400) 35, (F135-PW-600) conventional flight 34, powered lift 29.

Combustion Chamber: Short annular diffuser/combustor, derived from F119. Outer casing including HPT nozzle ring (lighter and less costly than in previous P&W fighter engines), handling airflow at 4,150 kPa (600 lb/sq in) at 649°C (1,200°F), and containing air-conditioning connections and inspection ports. Liner with impingement and film cooling containing Floatwall ceramic-coated nickel-based cast segments, each containing "thousands of holes", which "float" from their anchored location. Intense combustion with fuel/air ratio 20 per cent higher than in F100 engine to give near-record gas temperature exceeding 2,200°C (4,000°F).

HP Turbine: High-work single stage based on F119, with advanced airfoil coating and cooling derived from F119, but with cooling airflow doubled. Impingement cooling augmented by closing down rear stator angles. Nozzle ring organic-matrix vanes. The rotor comprises a main disk, miniature disk and cover plates, all incorporating the same high-strength powder-metallurgy (sintered) high-rotor blades of second-generation single-crystal Ni-based alloy, with advanced outer air seals. The HPT rotates at speeds exceeding 15,000 rpm, generating 47,725 kW (64,000 shp) from gas at just over 1,649°C (3,000°F), cooled by air supplied at 538°C (1,000°F) from the HPC. To minimise pressure loss the rotor blades are cooled by Tangential On-Board Injection (TOBI), each blade being a complex casting with multiple cooling passages. Growth in blade-tip diameter is controlled by a unique slow-responding thermally isolated support ring in materials selected for their low thermal expansion, giving passive clearance control through the normal engine-operating range.

LP Turbine: Two-stage design giving significantly greater shaft power than the single-stage LPT of the F119. Rotates in opposition to the HP turbine. Typical of the simplified design of the F135 are the main shaft bearings, (see note under HP compressor), and it is possible that the full production F135 may have a corrosion-resistant ceramic (silicon nitride) bearing. In the F135-PW-600 the LPT torque is transmitted through the fan and a dry-plate clutch to the LiftFan drive shaft, the turbine power being shared by the two driven items. Casing fabricated in refractory nickel and Pratt & Whitney proprietary materials. Supports aft-bearing compartment, whilst diffusing and turning the 1,093°C (2,000°F) efflux with minimum pressure loss (see next).

Afterburner: Large-volume with advanced flame-holder system. Fully variable convergent/divergent nozzle, with 15 hydraulically driven hinged flaps, controlling propulsive jet at 621 kPa (90 lb/sq in) at up to 1,927°C (3,500°F). Unique pressure-balance system to assist the hydraulic actuators which vary area and profile, and also to assist bypass air to reduce area when maximum loads are encountered. In the F135-PW-600 the complete nozzle can vector through 95° in 2.5 seconds to give 80.34 kN (18,000 lb st) lift force for STOVL. The Dash-100 and -400 LO axi-symmetric nozzle; The Dash-600 3BSM (three-bearing swivel module) has shorter variable flaps. It was designed to be able to bolt directly on to the STOVL version of the rival F136-GE-600 engine.

Accessories: Accessory gearbox driven off main HP shaft. Integrated Power Package (IPP) comprises the engine-start system and the F-35's Auxiliary Power Unit (APU). Dual fixed-displacement vane-type fuel pumps (the gear-type originally used added too much heat), with servo valves. Fuel/oil heat exchanger. Advanced prognostic and on-condition health-management systems. Commercially developed fire containment system.
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