Talk:Pratt & Whitney F135

message: There are a couple spots here that sound a little off to me.
"The F135 propulsion system already proved that it can meet these diverse requirements, during preliminary flight testing of the Boeing X-32 and Lockheed Martin X-35 aircraft in 2000."
I think this can be reworded to say something like "The F135 first flew as the engine that powered both of the JSF competitiors, the Boeing X-32 and the Lockheed Martin X-35".''
I also think the following line should be removed; the article is about the engine, not the F-35.
"As planned, new F-35 aircraft will replace the F-16 Fighting Falcon, AV-8B Harrier II, and F/A-18 Hornet." 
Also, I think this paragraph (below) needs to be rewritten a bit:
"Propulsion system support and maintainability are further enhanced by the F135's maintenance-focused design. It has approximately 40 percent fewer parts, which also improves reliability. All line-replaceable components (LRCs) can be removed and replaced with a set of six common hand tools. And, the F135 has a 50 percent lower infrastructure support requirement compared to current engines. The F135 produces 40,000 lbf (180 kN) of thrust,[1] the most ever in a fighter engine.[2]"
Any thoughts? - SidewinderX (talk) 20:23, 28 July 2009 (UTC)
replies: text: Go for it. Most of that sounds like brochure wording, as some users tend to just copy in sections from company sources. - - BilCat (talk) 01:33, 29 July 2009 (UTC)

text: Agreed, those changes are good. -Fnlayson (talk) 01:40, 29 July 2009 (UTC)
thread_title: Neutrality?

message: I've started to rework this article. My main goals are to flesh out the technical information based on what's available, do a better job of citing, and rewrite the sections that read like they're press release copy (which they are).I would also like to add more images. Feel free to point out specific areas that need help. Thanks! SidewinderX (talk) 13:46, 29 July 2009 (UTC)
replies: text: 100% of the thrust goes vertical so the lift fan is acting as a pure additive to the main engine thrust. Hcobb (talk) 16:39, 10 August 2009 (UTC)
replies: text:  Hmm, your rewording is better, but I still don't like what it's implying, and there are a few "errors" IMO. First, afterburning flight isn't always supersonic flight; rewording that to say afterburing thrust (or wet thrust) would be better I think. I also think that stating that the lift fan uses no additional fuel and generates no additional heat is unsourced at best or just wrong at worst. I'm not sure if the engine uses more fuel or not when the clutch engages for the lift fan. I'm sure it doesn't use as much as the afterburer (which is what you seem to want to say), but it's definitly possible it uses more fuel to keep the LP sections turning. Secondly, it definitly generates more heat. Not in the way that you seem to mean (afterburner exhaust heat), but turning all those parts and compressing/blowing air through the lift fan definitly generates more heat. I think you're just trying to make the point that the lift fan adds a lot of thrust to the engine for STOVL, which is true, but I don't think you're going about it the best way. Just leave the line about how much thrust that STOVL system generates compared to the wet thrust and that is fine IMO. (wow that was long, sorry) SidewinderX (talk) 20:07, 10 August 2009 (UTC)

text: I apologize for the lack of turbofan function in the File:JetEngineGraph-LiftFan.PNG, but it is kinda hard to show both mixed (turbofan) and unmixed (turbojet/turboshaft) functions in the same engine. The F135 engine and LiftSystem concepts are complex and not easily understood, and give rise to many misunderstandings and false assumptions. I have tried to show a different angle with that diagram and the File:LiftThrust-small1.PNG, but I would like a discussion on how to present the engine more clearly. The LiftSystem article does not allow F135-functions to be included, but I do not think they can be separated, as the dual power cycle of the F135 is critical for the operation of LiftSystem. TGCP (talk) 11:08, 22 May 2010 (UTC)
thread_title: Current Rework (Jul 09)

message: I have started a bit of work on the design section and I'm trying to be respectful of the original author's contributions, but I'm having a bit of trouble. It mostly reads (as pointed out earlier by BilCat) like brochure copy, and that's what I'm guessing it's from. That said, I'm sure there's some useful info in there, but I just don't understand some of it. For example the paragraph that starts "A feature of the F135 STOVL engine is flow multiplication...". I think that's talking about just the lift fan system, but I'm not sure. Any idea how to reword that, or should I just bulk rewrite it? SidewinderX (talk) 15:12, 10 August 2009 (UTC)
replies: text: 100% of the thrust goes vertical so the lift fan is acting as a pure additive to the main engine thrust. Hcobb (talk) 16:39, 10 August 2009 (UTC)
replies: text:  Hmm, your rewording is better, but I still don't like what it's implying, and there are a few "errors" IMO. First, afterburning flight isn't always supersonic flight; rewording that to say afterburing thrust (or wet thrust) would be better I think. I also think that stating that the lift fan uses no additional fuel and generates no additional heat is unsourced at best or just wrong at worst. I'm not sure if the engine uses more fuel or not when the clutch engages for the lift fan. I'm sure it doesn't use as much as the afterburer (which is what you seem to want to say), but it's definitly possible it uses more fuel to keep the LP sections turning. Secondly, it definitly generates more heat. Not in the way that you seem to mean (afterburner exhaust heat), but turning all those parts and compressing/blowing air through the lift fan definitly generates more heat. I think you're just trying to make the point that the lift fan adds a lot of thrust to the engine for STOVL, which is true, but I don't think you're going about it the best way. Just leave the line about how much thrust that STOVL system generates compared to the wet thrust and that is fine IMO. (wow that was long, sorry) SidewinderX (talk) 20:07, 10 August 2009 (UTC)

text: I apologize for the lack of turbofan function in the File:JetEngineGraph-LiftFan.PNG, but it is kinda hard to show both mixed (turbofan) and unmixed (turbojet/turboshaft) functions in the same engine. The F135 engine and LiftSystem concepts are complex and not easily understood, and give rise to many misunderstandings and false assumptions. I have tried to show a different angle with that diagram and the File:LiftThrust-small1.PNG, but I would like a discussion on how to present the engine more clearly. The LiftSystem article does not allow F135-functions to be included, but I do not think they can be separated, as the dual power cycle of the F135 is critical for the operation of LiftSystem. TGCP (talk) 11:08, 22 May 2010 (UTC)
thread_title: Design Section

message: The wording you added seemed misleading to me. While the total thrust in STOVL is close to wet thrust in conventional mode, they're not comparable. 20,000lbf of that lift is coming from the lift fan, which in the vertical axis, not the horizontal. Comparing that to the afterburning thrust is misleading because that liftfan thrust isn't used to propel the aircraft forward. Maybe that paragraph in the article needs to be rewritten to clarify that that thrust is basically in the vertical direction, not the horizontal. SidewinderX (talk) 16:08, 10 August 2009 (UTC)
replies: text: 100% of the thrust goes vertical so the lift fan is acting as a pure additive to the main engine thrust. Hcobb (talk) 16:39, 10 August 2009 (UTC)
replies: text:  Hmm, your rewording is better, but I still don't like what it's implying, and there are a few "errors" IMO. First, afterburning flight isn't always supersonic flight; rewording that to say afterburing thrust (or wet thrust) would be better I think. I also think that stating that the lift fan uses no additional fuel and generates no additional heat is unsourced at best or just wrong at worst. I'm not sure if the engine uses more fuel or not when the clutch engages for the lift fan. I'm sure it doesn't use as much as the afterburer (which is what you seem to want to say), but it's definitly possible it uses more fuel to keep the LP sections turning. Secondly, it definitly generates more heat. Not in the way that you seem to mean (afterburner exhaust heat), but turning all those parts and compressing/blowing air through the lift fan definitly generates more heat. I think you're just trying to make the point that the lift fan adds a lot of thrust to the engine for STOVL, which is true, but I don't think you're going about it the best way. Just leave the line about how much thrust that STOVL system generates compared to the wet thrust and that is fine IMO. (wow that was long, sorry) SidewinderX (talk) 20:07, 10 August 2009 (UTC)

text: I apologize for the lack of turbofan function in the File:JetEngineGraph-LiftFan.PNG, but it is kinda hard to show both mixed (turbofan) and unmixed (turbojet/turboshaft) functions in the same engine. The F135 engine and LiftSystem concepts are complex and not easily understood, and give rise to many misunderstandings and false assumptions. I have tried to show a different angle with that diagram and the File:LiftThrust-small1.PNG, but I would like a discussion on how to present the engine more clearly. The LiftSystem article does not allow F135-functions to be included, but I do not think they can be separated, as the dual power cycle of the F135 is critical for the operation of LiftSystem. TGCP (talk) 11:08, 22 May 2010 (UTC)
thread_title: LiftFan Thrust (HCobb)

message: I've made a couple of changes to rationalize the failure details since they were based on a few poorly worded sources as well as poor interpretation of the source in one instance. Hope that's ok.Pieter1963 (talk) 20:12, 1 January 2015 (UTC)
thread_title: Development

message: This section was a bit disjointed, I think, because it is made up from contributions from many editors. I have tried to tidy it up still keeping those contributions except:
removed statements which gave a personal interpretation of what is described in cited sources, removed sales brochure-type terminology, removed duplicated details.Pieter1963 (talk) 23:12, 28 January 2015 (UTC)
thread_title: Design

message: Nothing on unit cost except for "continuing the unit cost decreases," "substantial cost growth," and "below the cost of the F119"?
Decreases from what number?  Growth from what number?  What (number) below what other number?  — Preceding unsigned comment added by 144.183.224.2 (talk) 21:59, 27 August 2015 (UTC)
thread_title:  Unit Cost - Numbers? 

message: https://www.defensenews.com/air/2021/02/12/an-engine-shortage-is-the-newest-problem-to-hit-the-f-35-enterprise/
Why is this not notable? Hcobb (talk) 16:31, 24 February 2021 (UTC)
thread_title:  "serious readiness problem" 

message: I've been trying to find out what fuel is used in the F-35B engine and I've not had much luck. I've heard both JP-5 and JP-8 but no search seems to come up with a result. They talk about thrust & weight but never about fuel type. Is there a source I'm missing and shouldn't it be either on the engine page or the F-35 page? CycloneSteve (talk) 03:31, 20 December 2023 (UTC)
replies: text: The popular answer seems to be JP-8/F-34 which is supported by this photo of an F-35 being refuelled. Fuel type is a parameter of Template:Jetspecs but it's only meant for generic Avgas/Avtur types apart from a few exceptions that use exotic fuel like JP-7. One reason that fuel types are not generally listed in aircraft or aircraft engine articles even when known is that it could break WP:NOTGUIDE/WP:NOTMANUAL, we don't want ground crews and pilots checking Wikipedia for servicing their aircraft! Nimbus (Cumulus nimbus floats by) 15:00, 20 December 2023 (UTC)
thread_title:  Fuel used for this engine