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62-672: Developed from the Pratt & Whitney F119 engine used on the F-22 Raptor , the F135 produces around 28,000 lbf (125 kN) of thrust and 43,000 lbf (191 kN) with afterburner. The F135 competed with the General Electric/Rolls-Royce F136 to power the F-35. The F135 originated with Lockheed Corporation Skunk Works , with efforts to develop a stealthy STOVL strike fighter for

124-521: A demonstrator engine. The ground test demonstrator used the first stage fan from a F119 engine for the lift fan. The engine fan and core from the F100-PW-220 were used for the core of the demonstrator engine, and the larger low-pressure turbine from the F100-PW-229 was used for the low-pressure turbine of the demonstrator engine. The larger turbine was used to provide the additional power required to operate

186-540: A design life of 8,650 total accumulated cycles, with inspection and overhaul of the hot section approximately every 2,000 hours and the cold section every 4,000 hours. While the production F119 on the F-22 incorporates rectangular thrust vectoring nozzles, prototype variants on other aircraft had different nozzle solutions that are tailored to the airframe. The YF119 on the YF-23 had a single-expansion ramp nozzle (SERN) consisting of

248-449: A ground test. It was to be replaced by a solid part adding 6 lb (2.7 kg) in weight. In 2013, a former P&W employee was caught attempting to ship "numerous boxes" of sensitive information about the F135 to Iran. Despite the troubles, the 100th engine was delivered in 2013. LRIP-6 was agreed in 2013 for $ 1.1 billion for 38 engines of various types, which helped to decrease the unit cost. Air Force Lt. Gen. Christopher C. Bogdan,

310-462: A requirement for an upgraded engine, Pratt and Whitney had cooperated with the US Navy on a two-block improvement plan for the F135 engine. The goals of Block 1 are a 7–10% increase in thrust and a 5–7% lower fuel burn. The plans include better cooling technology for turbine blades; this would increase the longevity of the engine and substantially reduce maintenance costs. The goal of Block 2 is to work with

372-561: A source for crack initiation and subsequent propagation. Efficiency improvements of up to 8% are possible. Any damage to integrally bladed rotor blades beyond minor dents requires the full removal of the engine so that the rotor may be replaced or, if possible, replacement blades welded on. Maintenance of this nature cannot be done on the flightline and often must be performed at a specialized facility. Integrally bladed rotor blades must undergo rigorous harmonic vibration testing as well as dynamic balancing to an extremely high standard, since

434-486: A variable wedge flap on the top and a fixed ramp on the bottom, which then transitions to a trench on top of the aft fuselage. While the SERN lacked thrust vectoring capability, it allowed the exhaust to be further cooled in the trenches, significantly reducing infrared signature when viewed from below the aircraft; the trenches in the aft deck were lined with tiles that were " transpiration cooled " from engine bleed air to withstand

496-407: Is a turbomachine component comprising both rotor disk and blades as a single part instead of a disk assembled with individual removable blades. Blisks generally have better aerodynamics than conventional rotors with single blades and are lighter. They may be additively manufactured, integrally cast, machined from a solid piece of material, or made by welding individual blades to a rotor disk. The term

558-606: Is a major objective for the F135. The engine has fewer parts than similar engines, which improves reliability. All line-replaceable components (LRCs) can be removed and replaced with a set of six common hand tools. The F135's health management system is designed to provide real time data to maintainers on the ground. This allows them to troubleshoot problems and prepare replacement parts before the aircraft returns to base. According to Pratt & Whitney, this data may help drastically reduce troubleshooting and replacement time, as much as 94% over legacy engines. Prior to any services issuing

620-431: Is a primary driver for the increased potential problem notifications." A&P Alloys stated that they stood behind their product even though they were not given access to the parts to do their own testing. Tracy Miner, an attorney with Boston-based Demeo LLP representing A&P Alloys said, "it is blatantly unfair to destroy A&P’s business without allowing A&P access to the materials in question" In July 2014 there

682-556: Is an afterburning turbofan engine developed by Pratt & Whitney for the Advanced Tactical Fighter (ATF) program, which resulted in the Lockheed Martin F-22 Raptor . The engine delivers thrust in the 35,000 lbf (156 kN) class and was designed for sustained supersonic flight without afterburners, or supercruise . Delivering almost 22% more thrust with 40% fewer parts than its F100 predecessor,

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744-568: Is expected to begin in 2010. This redesign has caused "substantial cost growth". P&W expected to deliver the F135 below the cost of the F119, even though it was a more powerful engine. However, in February 2013 a cracked turbine blade was found during a scheduled inspection. The crack was caused by operating at high turbine temperatures for longer periods than usual. In December 2013 the hollow first stage fan blisk failed at 77% of its expected life during

806-541: Is obtained from a two-stage lift fan (about 46%) in front of the engine, a vectoring exhaust nozzle (about 46%), and a nozzle in each wing using fan air from the bypass duct (about 8%). These contributions to the total lift are based on thrust values of 18,680 lbf (83.1 kN), 18,680 lbf (83.1 kN) and 3,290 lbf (14.6 kN) respectively. Another source gives thrust values of 20,000 lbf (89 kN), 18,000 lbf (80 kN), and 3,900 lbf (17 kN) respectively. In this configuration most of

868-474: Is used mainly in aerospace engine design. Blisks may also be known as integrally bladed rotors ( IBR ). Blisk manufacturing has been used since the mid-1980s. It was first used by Sermatech-Lehr (now known as GKN Aerospace ) in 1985 for the compressors of the T700 helicopter engine. Since then, its use has continued to increase in major applications for both compressors and fan blade rotors. Examples include

930-617: The F100 's compressor. The high pressure and low pressure turbines were single stage and counter-rotating, which reduced the gyroscopic forces on the engine; it was hoped that counter-rotation would eliminate a row of turbine stators for a vaneless high and low pressure turbine interface, which would save weight and reduce parts count, but this was ultimately not successful and the stators were retained. The fan and compressor stages were to use integrally bladed rotors (IBR), also known as blisks, to reduce weight and cost and improve performance. Owing to

992-590: The U.S. Marine Corps under a 1986 DARPA project under the auspices of the Advanced STOVL (ASTOVL) program, an early progenitor of the Joint Strike Fighter (JSF) that resulted in the F-35. Lockheed engineer Paul Bevilaqua developed and eventually patented a concept aircraft and a propulsion system called the Shaft-Driven Lift Fan (SDLF), and then turned to Pratt & Whitney (P&W) to build

1054-540: The -100 and the -600 versions. A -400 version is mentioned, similar to the -100, the main difference being the use of salt-corrosion resistant materials. The -600 is described below with an explanation of the engine configuration changes that take place for hovering. The engine and Rolls-Royce LiftSystem make up the Integrated Lift Fan Propulsion System (ILFPS). The vertical thrust for the STOVL version

1116-693: The 30,000 lbf (133 kN) class for an aircraft gross weight of 50,000 lb (22,700 kg). Pratt & Whitney and General Electric were selected to make prototype engines, designated YF119 and YF120 respectively, for demonstration and validation (Dem/Val). Both engine makers would provide engines for both the Lockheed/Boeing/General Dynamics YF-22 and the Northrop/McDonnell Douglas YF-23 ATF technology and flight demonstrators. The ATF's increasing weight during development required more thrust to meet

1178-508: The ATF's demanding requirements for supercruise, the PW5000 design has low bypass ratio, high core and turbine inlet temperatures, and a fully variable convergent-divergent nozzle to achieve high specific thrust in intermediate, or non-afterburning power. The combustor, internally named Floatwall, eliminated welds to mitigate crack growth due to thermal cycling. The original RFP called for maximum thrust in

1240-499: The ECU for further development and fielding by 2029 to support the F-35's Block IV upgrade. Data from Pratt & Whitney, Technical Order TO-00-85-20, American Society of Mechanical Engineers Data from Pratt & Whitney, TO-00-85-20, American Society of Mechanical Engineers Related development Comparable engines Related lists Pratt %26 Whitney F119 The Pratt & Whitney F119 , company designation PW5000 ,

1302-779: The F119 Heavy Maintenance Center (HMC) at Tinker Air Force Base, Oklahoma in the first F119 depot overhaul. Turbine engine advances from ATEGG and JTDE continued with the Integrated High Performance Turbine Engine Technology (IHPTET) program, with applications in F119 improvement packages and derivatives. Prototype YF119 variants powered the Boeing X-32 and Lockheed Martin X-35 Joint Strike Fighter (JSF) concept demonstrator aircraft, and subsequent full scale development of

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1364-479: The F119 allows the F-22 to achieve supercruise speeds of up to Mach 1.8. The F119's nozzles incorporate thrust vectoring that enable them to direct the engine thrust ±20° in the pitch axis to give the F-22 enhanced maneuverability. The F119 is also the basis for the Joint Strike Fighter (JSF) propulsion system, with variants powering both the Boeing X-32 and Lockheed Martin X-35 concept demonstrators. The X-35 won

1426-567: The F119 derivative resulted in the F135 family of engines that powers the Lockheed Martin F-35 Lightning II . The F119 is a twin-spool axial-flow low-bypass turbofan. It has a three-stage fan driven by a single-stage low pressure turbine and six-stage high pressure compressor driven by single-stage high pressure turbine. The shroud-less fan has wide-chord, low aspect ratio hollow titanium fan blades that are linear-friction welded to

1488-493: The F119-PW-100 in order to achieve high specific thrust . The F119 has dual-redundant full authority digital engine control ( FADEC ), also referred to internally as Digital Electronic Engine Control (DEEC), supplied by Hamilton Standard and fully integrated into the F-22's vehicle management system, making the engine highly reliable, stall-resistant, and forgiving of rapid throttle inputs. The three-zone (reduced from four from

1550-416: The F135 is providing vertical lift using the increased bypass ratio from the lift fan, the thrust augmentation is 50% with no increase in fuel flow. Thrust augmentation is 52% in conventional flight when using the afterburner, but with a large increase in fuel flow. The transfer of approximately 1 ⁄ 3 of the power available for hot nozzle thrust to the lift fan reduces the temperature and velocity of

1612-481: The General Electric's variable cycle YF120, Pratt & Whitney accrued far greater test hours and emphasized reliability and the lower risk. Ground tests of the F119-PW-100 were first conducted in February 1993. The production engines were fitted on the production F-22 , and were first flown on the F-22's maiden flight on 7 September 1997. A total of 507 engines were produced. In 2013 Pratt & Whitney assisted

1674-711: The JSF competition and the production Lockheed Martin F-35 Lightning II is powered by an F119 derivative, the Pratt & Whitney F135 which produces up to 43,000 lbf (191 kN) of thrust. The F119 resulted from the Joint Advanced Fighter Engine (JAFE) program in the early 1980s aimed at supplying the powerplant for the Air Force's Advanced Tactical Fighter (ATF). Detailed design of Pratt & Whitney's submission, designated internally as PW5000, began when

1736-519: The Joint Advanced Strike Technology (JAST), which was renamed JSF in 1995; under the JSF program, contracts for flightworthy concept demonstrator aircraft were awarded in 1996 to Lockheed Martin and Boeing for the air vehicle designs and P&W for the initial propulsion system. P&W developed the JSF engine from their F119 turbofan, which powers the F-22 Raptor , as the "F119-JSF". A flightworthy prototype system that incorporated

1798-470: The LP rotor and a clutch. The engine operates as a separate flow turbofan with a higher bypass ratio. The power to drive the fan—about 30,000 shp (22,000 kW)—is obtained from the LP turbine by increasing the hot nozzle area. A higher bypass ratio increases the thrust for the same engine power as a fundamental consequence of transferring power from a small diameter propelling jet to a larger diameter one. When

1860-849: The Rocketdyne RS-68 rocket engine and the General Electric F110 turbofan. The F-35B variant of the Joint Strike Fighter uses blisks to achieve short take-off and vertical landing . Engine manufacturer CFM International is using blisk technology in the compressor section of its LEAP-X demonstrator engine program, which has completed full-scale rig testing. PowerJet SaM146 engines used on Sukhoi Superjet 100s are also equipped with blisks. General Electric 's Passport (formerly "TechX") engine uses blisks for both its main 52" fan as well as for 5 of its 10 high pressure compressor stages. The GEnx already uses blisks in some stages. Instead of making bare compressor disks and attaching

1922-574: The STOVL aircraft. Hamilton Sundstrand is responsible for the electronic engine control system, actuation system, PMAG, gearbox, and health monitoring systems. Woodward, Inc. is responsible for the fuel system. The F135 is assembled at a plant in Middletown, Connecticut . Some parts of the engine are made in Longueuil , Quebec, Canada, and in Poland. The first production propulsion system for operational service

Pratt & Whitney F135 - Misplaced Pages Continue

1984-548: The US Air Force's Adaptive Engine Transition Program , with the intention of introducing technology for an engine rated at 45,000 lb of thrust, to be used in a sixth-generation fighter. Pratt & Whitney's upgrade path for the F135 would change several times, with Block 1 and 2 initially becoming Growth Option 1 and 2. At the end of May 2017 Pratt and Whitney announced the F135 Growth Option 1 had finished testing and

2046-504: The X-32 for the JSF competition and the YF119-611 would form the basis for the F135, which integrates the F119 core with new components optimized for the JSF. The F135 team is made up of Pratt & Whitney , Rolls-Royce and Hamilton Sundstrand . Pratt & Whitney is the prime contractor for the main engine, and systems integration. Rolls-Royce is responsible for the vertical lift system for

2108-419: The alternate F136 engine program, but Congress has maintained program funding. As of 2009, P&W developed a more durable version of the F135 engine to increase the service life of key parts. The life expectancy of the parts was reduced because the hot sections of the engine (combustor and high-pressure turbine blades specifically) ran hotter than expected. The test engine is designated XTE68/LF1 , and testing

2170-399: The blades later, blisks are single elements combining the two. This eliminates the need to attach the blades to the disk (via screws, bolts, etc.), thus decreasing the number of components in the compressor, while at the same time decreasing drag and increasing efficiency of air compression in the engine. The elimination of the dovetail attachment found on traditional turbine blades eliminates

2232-408: The bypass flow is ducted to the wing nozzles, known as roll posts. Some is used for cooling the rear exhaust nozzle, known as the 3-bearing swivel duct nozzle (3BSD). At the same time an auxiliary inlet is opened on top of the aircraft to provide additional air to the engine with low distortion during the hover. The low pressure (LP) turbine drives the lift fan through a shaft extension on the front of

2294-420: The clean burning of the fuel and reduced NOx generation. Within the turbine exhaust case, the high-pressure turbine blades are made of single-crystal superalloys and impingement cooled using air from the high-pressure compressor. The high and low pressure spools are counter-rotating. The requirement for the ATF to supercruise, or fly supersonic without afterburners, results in a very low bypass ratio of 0.30 for

2356-450: The damage and wear are within thresholds set by the design authority, it is possible that the blisks can be repaired. Repair of blisk components is complex and first requires an accurate 3D representation of the component. The quickest way to do this is by 3D scanning the product. After the part is scanned, an STL file (stereolithograph) can be passed to a CNC code generating software such as NX CAM . The tool paths are regenerated to suit

2418-406: The disks to form single-piece integrally-bladed rotors (IBRs), or blisks. The fan and compressor stators and thrust-vectoring nozzle use a burn-resistant titanium alloy called Alloy C, with the first row of vanes variable in order to increase stall and surge margin. The Floatwall annular combustor is lined with high-cobalt material for oxidation resistance and combustion chamber durability, and ensures

2480-407: The executive officer of the F-35 program, has called out P&W for falling short on manufacturing quality of the engines and slow deliveries. His deputy director Rear Admiral Randy Mahr said that P&W stopped their cost-cutting efforts after "they got the monopoly". In 2013 the price of the F135 increased by $ 4.3 billion. In May 2014, Pratt & Whitney discovered conflicting documentation about

2542-497: The exhaust plume and facilitating its mixing with ambient air through shed vortices. The F119 places a high emphasis on human systems integration ; features that facilitate engine maintenance and servicing include modular design such as an axially split case, color-coded cables and harnesses, and a reduction of the number of hand tools required for servicing to just five. Most components are one-deep and servicing can be conducted while wearing hazmat protective clothing. The engine has

Pratt & Whitney F135 - Misplaced Pages Continue

2604-422: The final blisk shape. The measurement and inspection of blisks is crucial for guaranteeing engine performance carried out at the end of the manufacturing processes. Traditionally this has been achieved using tactile devices, like coordinate-measuring machines (CMM), but as geometries and requirements increase, the trend in modern factories is to carry out 3D scanning inspection systems. This has advantages of

2666-554: The heat of the exhaust. The specialized YF119 variants on the X-32 and X-35 had provisions for short takeoff and vertical landing (STOVL) operations. The YF119-PW-614 on the X-32 had a pitch-axis thrust vectoring nozzle and valves can redirect the engine exhaust and bleed air to provide direct lift, similar to the Pegasus engine on the Harrier . In contrast, YF119-PW-611 on the X-35 had a round axisymmetric nozzle that can swivel downwards while

2728-545: The lift fan through the low-pressure spool shaft, which would be engaged by a clutch in STOVL mode. Finally, a variable thrust deflecting nozzle was added to complete the "F100-229- Plus " demonstrator engine. This ground demonstrator engine proved the shaft-driven lift fan concept and led to the development of the eventual JSF engine. ASTOVL continued under the Common Affordable Lightweight Fighter (CALF) program in 1993 before eventually being merged into

2790-577: The low-pressure spool drives a lift fan that's engaged through a clutch; engine bypass air is also routed to roll posts for additional lift and stability. The X-35 won the JSF competition and its shaft-driven lift fan system, called LiftSystem , was fully developed by Rolls-Royce and Pratt & Whitney for the F135-PW-600. Data from Pratt & Whitney, RAND, Aviation Week, USAF. Related development Comparable engines Related lists Blisk A blisk ( portmanteau of bladed disk )

2852-400: The material limit of 540 °C (1,000 °F). Micro cracks appeared in third-stage fan blades, according to program manager Christopher Bogdan, causing blades to separate from the disk. The failed blades punctured a fuel tank and hot air mixing with fuel caused the fire. As a short term fix, each aircraft is flown on a specific flight profile to allow the rotor seal to wear a mating groove in

2914-401: The natural damping of the dovetail attachment of a typical turbine blade is no longer present. Blisks can be produced with several different manufacturing processes, including CNC milling, investment casting , electro chemical machining , 3D printing , or welding . Research is being conducted to produce them using friction welding of "near net" part shapes that are then machined down to

2976-481: The origin of titanium material used in some of its engines, including the F135. The company assessed that the uncertainty did not pose a risk to safety of flight but suspended engine deliveries as a result. Bogdan supported P&W's actions and said the problem was now with A&P Alloys, the supplier. The US Defense Contract Management Agency wrote in June 2014 that Pratt & Whitney's "continued poor management of suppliers

3038-488: The performance requirements; as gross weight grew to 60,000 lb (27,200 kg), the required maximum thrust was increased by 20% to 35,000 lbf (156 kN) class. Pratt & Whitney's design changed to incorporate a 15% larger fan, increasing bypass ratio from 0.25 to 0.30. However, unlike General Electric, Pratt & Whitney did not fit its larger fan on flightworthy YF119s for the ATF flight demonstrators to avoid potential reliability issues that may arise. Instead,

3100-474: The pitch axis, greatly improving the aircraft's pitch authority by augmenting the pitching moment of the tail with engine thrust; this enables the F-22 to remain controllable while flying at a trimmed alpha of over 60°. The thrust vectoring is fully integrated into the F-22's flight control system to facilitate handling. The rectangular nozzle's divergent section consists two wedge-shaped flaps for stealth and also contribute to lower infrared signature by flattening

3162-477: The prototype) afterburner, or augmentor, contributes to the stealth of the aircraft by having fuel injectors integrated into thick curved vanes coated with ceramic radar-absorbent materials (RAM). These vanes replace the traditional fuel spray bars and flame holders and block line-of-sight of the turbines. The rectangular convergent-divergent nozzle is fully variable for both the convergent throat and divergent areas for high nozzle pressure ratio and can vector ±20° in

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3224-451: The rear lift jet impinging on the ground. The F-35 can achieve a limited 100% throttle cruise without afterburners of Mach 1.2 for 150 miles (240 km; 130 nmi). Like the F119, the F135 has a stealthy augmentor where traditional spray bars and flameholders are replaced by thick curved vanes coated with ceramic radar-absorbent materials (RAM). Afterburner fuel injectors are integrated into these vanes, which block line-of-sight of

3286-670: The request for proposals (RFP) for JAFE, later renamed the ATF Engine (ATFE) program, was released in May 1983. Advances in engine technology, such as those from the Advanced Turbine Engine Gas Generator (ATEGG) and the Joint Technology Demonstration Engine (JTDE) programs, allowed the design to do more work with fewer stages, with the PW5000's compressor having only 6 stages compared to the 10 stages in

3348-726: The revised fan was extensively ground tested at Wright-Patterson Air Force Base. As a result, both the YF-22 and YF-23 had lower performance with the YF119s than with the YF120s. On 3 August 1991, Pratt & Whitney was awarded the EMD contract for ATF engine, while the Lockheed/Boeing/General Dynamics team won the contract for the ATF airframe. While the YF119 was a more conventional design compared to

3410-547: The shaft-driven lift fan, designated "YF119-PW-611", was tested on the Lockheed Martin X-35 concept demonstrator aircraft and first flew in 2000. P&W also made another prototype, the "YF119-PW-614", for the competing Boeing X-32 which had direct lift system. In flight tests, the X-35B was able to demonstrate STOVL by taking off in 500 ft (150 m), then flew supersonic before landing vertically. The X-35 concept beat

3472-442: The speed of measurement compared to tactile devices, whilst collecting 3D data to relate back to design characteristics. Using 3D data, parts can be catalogued in this way, often called digital twin , allowing monitoring of the product through its life-cycle. Engine-run blisks pose their own set of unique requirements. After parts have been in service in the engine, noticeable amounts of damage and wear will be observed. Provided that

3534-471: The stator to prevent excessive rubbing. Pratt & Whitney managed to meet their 2015 production goals, but "recurring manufacturing quality issues" in turbine blades and electronic control systems required engines to be pulled from the fleet. Derived from the F119 engine, the F135 is a mixed-flow afterburning turbofan utilizing a similar core as the F119 with a new fan and LP turbine. There are two F135 variants:

3596-550: The turbines, contributing to aft-sector stealth. The axisymmetric nozzle consists of fifteen partially overlapping flaps that create a sawtooth pattern at the trailing edge. This creates shed vortices and reduces the infrared signature of the exhaust plume. The effectiveness is reportedly comparable to that of the F119's wedge nozzles, while being substantially more cost effective and lower maintenance. The engine uses thermoelectric -powered sensors to monitor turbine bearing health. Improving engine reliability and ease of maintenance

3658-449: Was an uncontained failure of a fan rotor while the aircraft was preparing for take-off. The parts passed through a fuel tank and caused a fire, grounding the F-35 fleet. During high g-force maneuvering three weeks before the flight, flexing of the engine caused excessive rubbing at the seal between the fan blisk and the fan stator initiating the impending failure. The rub caused a temperature of over 1,000 °C (1,900 °F), well beyond

3720-686: Was available for production. The upgrade requires the changing of the power module on older engines during depot overhaul and can be seamlessly inserted into future production engines at a minimal increase in unit cost and no impact to delivery schedule. The Growth Option 1 offers an improvement of 6–10% thrust across the F-35 flight envelope while also getting a 5–6% fuel burn reduction. In June 2018, United Technologies , parent company of P&W, announced Growth Option 2.0 to help provide increased power and thermal management system (PTMS) capacity, providing options for operators for instance if they are wishing to upgrade to heavier weapons. Although Growth Option 2.0

3782-617: Was initially envisaged as a further development of the F135 with an adaptive fan to become the XA101 , a three-stream adaptive cycle engine , Pratt & Whitney has since split the XA101 as an entirely separate design with a new core, while Growth Option 1.0 would evolve to become the F135 Engine Enhancement Package (EEP), later renamed Engine Core Upgrade (ECU). In 2023, the USAF chose to fund

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3844-633: Was scheduled for delivery in 2007 with the purpose of serving the U.S., UK, and other international customers. The initial F-35s went into production with the F135 engines, but the GE / Rolls-Royce team planned to develop a replacement F136 engine in July 2009. In 2010, the Pentagon planned for the two propulsion systems to be competitively tendered. However, since 2006 the Defense Department has not requested funding for

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