power 40,000 pounds of trust kind  of power advanced power helping to  

defend a host of Nations and the Royal Air  Force with Pratt & Whitney long have been  

partners preserving freedom in fact our  engines have powered more than a dozen  

RAF aircraft platforms over the last  80 years including the f-35b lightning  

2 with the advanced F 135 engine the most  innovative fighter aircraft in the world

the fifth-generation F 135 continues  to redefine what's possible for our  

customers and their missions because  when Allied air forces like the RAF  

need dependable power we listen we  innovate we manufacture we go beyond

to today's game changing F 135 propulsion  system our people are driven by a passion  

to design and build the world's most dependable  engines with the most innovative technologies  

to redefine what's possible and provide  our customers with unmatched capabilities

today the f 135 stove for the f-35b lightning  2 is the most advanced operational adaptive  

engine ever produced able to transition  between hover and conventional flight at  

the push of a button and offering growth  options to meet tomorrow's threats head-on

as adversarial threat systems in the 21st century  continued to evolve new engine capabilities are  

required to keep our customers ahead of the  threat to achieve mission success now and in  

the future our customers must project airpower  at greater distances and overcome advanced air  

defenses they need to fly farther and faster  on missions that demand a seamless transition  

between high thrust and fuel efficiency without  trade-offs and they can't wait years for that  

adaptive capability they must address evolving  threats now at Pratt & Whitney we're developing  

and fielding a suite of unmatched adaptive  technologies at a pace that ensures our  

customers have the capabilities and options  they need to maintain an operational edge  

today and into the future these technologies go  beyond the demand modulated engine architecture  

and provide options for control systems power  and thermal management as well as sustainment  

capabilities to meet the demands of range  persistence survivability maintainability and  

advanced weapon systems with Pratt & Whitney's  future adaptive spiral technology approach fast  

these advanced technologies can be made available  to our customers faster through timely insertion  

into current and future platforms at Pratt &  Whitney adaptive is in our DNA it's a mindset  

that begins with our people and drives us to  go beyond to push the boundaries of military  

aircraft propulsion to build upon our legacy  of adaptive experience that spans seven decades  

to enable air dominance today tomorrow  and beyond go farther with adapt faster

cut and Whitney Zeff 135 propulsion system  for the fifth-generation f-35 lightning ii  

continues to redefine what's possible for  our customers but we're not stopping there  

we stand ready to take the world's most  advanced fighter engine to the next level  

with growth options to keep our customers ahead  of evolving threats cred and Whitney's growth  

options for the F 135 offer affordable variant  common upgrades that can be available to all  

f-35 program participants growth option  1.0 delivers a 5 to 6 percent fuel burn  

improvement and a 6 to 10 percent thrust  increase across the f-35 flight envelope  

it also enables up to a 5 percent increased  in powered lift thrust for the f-35 be very

growth option 2.0 incorporates the same fuel  burn and thrust improvements as growth option  

1.0 and also brings a significant improvement in  power and thermal management system capacity for  

the f-35 our spiral approach to next generation  propulsion technologies ensures our customers  

have the capabilities required to maintain the  operational edge now and into the future inside  

the f-35 s engines powering the fifth generation  engines aboard Lockheed Martin's next generation  

f-35 fighters have been almost 30 years in the  making Liam Stoker takes a look at the development  

of Pratt & Whitney's F 135 engine from its concept  to refinement and details its performance against  

foreign counterparts as various versions of  Lockheed Martin's fifth-generation fighter the  

f-35 approach advanced stages of flight testing  the aircraft is undergoing close scrutiny from  

curious onlookers one particular area of interest  is likely to be its custom-built lift fan engine  

developed by Pratt & Whitney using technology  patented by Lockheed Martin and produced by  

rolls-royce a rival to the F 135 the General  Electric and rolls-royce built F 136 had been  

in development up until December 2011 but was  dropped after the Pentagon refused to support  

further development capable of catering for  the demands of all three f-35 variations while  

ensuring an ease of maintenance and reduced  downtime the F 135 has taken almost 30 years  

of development but now looks ready to power the  future fighter of the US and a host of European  

nations development and origins of the F 135  engine Tora jhin's of the F 135 lion Lockheed  

Martin skunk works attempts to develop a stealthy  short takeoff and vertical landing stov L fighter  

for the US as part of DARPA say stov L program  in 1986 a concept aircraft and propulsion system  

was developed and patented by Lockheed chief  aeronautical scientist Paul Bevilaqua components  

from F 119 and f100 to 229 engines were used to  create the f-102 229 plus demonstrator engine  

which went on to prove bevilaqua's lift fam  concept and ultimately lead to the development  

of the f 135 for use on Lockheed Martin's f-35  the F 135 team responsible for the development  

of the engine consists of pratt & whitney  rolls-royce and Hamilton Sundstrand through  

production techniques and materials the F 135  is available at cheaper prices than the F 119  

despite being a more powerful engine TW o shaft  engine design of the F 135 and variations the F  

135 is a two shaft engine featuring a three-stage  fan and six stage high-pressure compressor the  

hot section comprises an annular combustor with  a single stage high-pressure turbine unit and  

a two-stage low-pressure turbine the engine's  afterburner also features a variable converging  

diverging nozzle three engine variants have  been designed the F 135 pw100 and F 135 PW  

400 for use aboard the conventional and carrier  versions of the aircraft respectively and the F  

135 PW 600 for the sto VL variation both the  conventional and carrier engines are largely  

similar and produce almost identical results  with a maximum wet thrust of 43,000 lbf and a  

dry thrust of 28,000 lbf the major difference is  the use of salt corrosion resistant materials in  

the carrier variant the stov l engine however is  capable of producing different results courtesy  

of its design and the demands placed upon  it enabling shorter vertical lift off with  

the stov l f-35 variant the stov l variation  of the f-35 to be used by the US Marine Corps  

in UK Royal Navy used Lockheed Martin's patented  rolls-royce lift system developed by rolls-royce

compost of a lift fan driveshaft to roll posts  into three bearing swivel module three BSM the  

system is responsible for allowing the vertical  liftoff required to operate aboard some aircraft  

carriers the three BSM acts is a thrust  vectoring nozzle allowing the exhaust to  

be directed downwards to enable vertical lift  off the lift fan located towards the front of  

the aircraft acts as a counterbalance by using  two counter-rotating BLISK s-- unheated engine  

the bypass air has been diverted to Anastas  mounted on the wings of the aircraft called

the system is capable of handling 18,000  lbf of dry trust to the 3 PS M 20,000 lb  

F to the lift fan and a further 3900  lb-ft both roll posts toddling 41,000  

trust the system developed purposefully for  the f-35 program received the Collier trophy  

for achievements in aeronautics in 2001 keeping  f-35s in the air reliability and maintenance one  

major directive of the development of the f100  35 engine was to drastically improve engine  

reliability and ease of maintenance over previous  aircraft keeping downtime at a minimum one such  

method was to use far fewer parts in comparison  to similar engines theoretically reducing parts  

failures and ensuring that all line replaceable  components can be changed using a standard set  

of six common tools the major leap forward  has however been the establishment of the F  

135 health management system which monitors  the performance of the engine automatically  

and provides real-time data to maintain errs on  the ground this data is analyzed before maintain  

errs troubleshoot n identify any necessary  replacement parts prior to the aircraft returning  

to base pratt & whitney has estimated that this  could save as much as ninety four percent of  

replacement time over legacy engines achieving  the directive of reducing aircraft downtime