F-35 Multirole Joint Strike Fighter

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rjmaz1

New Member
Frankly, most of the criticisms of the JSF is that it won't be a great interceptor, nevermind its sensors and stealthiness will allow the aircraft to shoot first. A sharper front end could make it a better interceptor, but to do so reduces its sensors and its internal bomb bay. Talk about a dog chasing its tail.

The aircraft was designed to be a multi-role aircraft, with an emphasis on bombing. Its turning out to be great at what it does. There is a reason why the engineers chose its length, its internal bomb bay, and the bluntness of its nose. Live with it.
Well said.

A sphere has the largest internal volume for any given weight. So the F-35's goal of being light and long ranged is reflected by its short and fat shape which gives it the largest internal volume. Even Mach 2+ capable aircraft cruise at subsonic speeds as it is much more efficient. The short and fat shape of the F-35 does not hinder performance at subsonic speeds. The large majority of the mission profiles will see the F-35 flying with extreme levels of efficiency that cannot be matched.


F119 vs F135
In relation to the discussion with other users regarding the F119 and F135. The differences of the engines from a design perspective are very slight. The F-135 has a slightly higher bypass ratio which is the reason for the diameter and thrust increase. The Hot section is still very similar in both engines.

The hot section has an air velocity much higher than the air bypassing the core. So an engine with a higher bypass ratio has more total thrust but the average velocity of that thrust is less, this is true with the F135. The speed of air exiting the engine is just as important as the amount of thrust when it comes to determining if an aircraft can supercruise. If the F119 engine in the F-22 is a Mach 1.8 capable engine then the F135 is atleast a Mach 1.5 capable engine in terms of exhaust velocity at dry thrust.

Whoever says that the F135 cannot supercruise because only the F119 factsheet mentions the word "supercruise" has NO idea what they are talking about.

Using some quasi logic: If the F135 was magically placed inside the F-22 the lower exhaust velocity would mean that it would fly slower than its current supercruise speed. The exhaust velocity of the F135 is not that much slower, so the F-22 will still supercruise fine with the F135. The supercruise speed might be Mach 1.5 instead of Mach 1.8, however the extra thrust output may make up for some of the speed reduction and push the F-22's supercruise speed up to Mach 1.6 with the F135. For the F135 to be placed inside an F-22 and it not being able to exceed Mach 1 without afterburners is illogical.

The F135 is a supercruise capable engine. No if's or buts. Of course it is not in the USAF's best interests to claim the F-35 as a supercruising fighter as it will put the nail in the coffin for the F-22. However such claims would be highly benificial for such threads like this as it would prove that the F-35 is without a doubt the best option for Australia.

That said the F-35 has thrust to weight ratio that is only 20% lower than the F-22 at dry thrust levels and a exhaust velocity that at most would be 20% slower. Damn the F-35 will still be fast!

My guess is Mach 1.3 without afterburner and fuel internal combat load. Anyone wanna place bets?

That makes it the third fastest and worlds longest ranged fighter, Who said it wont be a good interceptor?
 
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Feanor

Super Moderator
Staff member
Actually the F-35A and F-35B are much closer than the MiG-29 and MiG-35. Both aircraft (and the F-35C) are completely identical except for those components needed to allow for the differing takeoff and landing profiles of the various versions. For example all the F-35 versions share the same combat systems, the same tails, the same centre afts and so on. Most of their spare parts will be the same and it will be very simple to convert from one platform to the other. They are also produced side by side on the same production line.

This is far more alike than different block upgrades of the same aircraft, for example the MiG-29S and MiG-35. Where not only new systems are added but many are changed because subcomponents are no longer available. There is also a lot more standardisation on a computer controlled production line like the F-35s compared to the old 'bang em' together type production line used for the FULCRUMs.
So Future Tank was correct when he said that the JSF program was intended to unify the USAF and USN airwings to a somewhat standardized form and thus save money both on maintenance and development?
 

cobzz

New Member
F135 is derived from the F119 not the F110. :)

6. No internal gun on F-35B. - This is even crazier that the weapons bays. I don't understand which Marine pilot is going to fly what is essentially a CAS role aircraft without an internal gun
You mean like the Harrier?

Before you turn this into some sort of miracle, the F-16 was powered initially by the Pratt & Whitney JTF22 (F100) but was later changed to the General Electric F110.
F-16 is mix of F100 and F110 engines... even newer aircraft are F110-129 or F100-229. The F-15 is P&W engines; only F110 powered F-15's are export.

Why can't you just say that the F135 has a larger fan! So what? That's not a different engine!
Neither is the CFM-56 on the 737 any different to the GE F101 or F110?
 

FutureTank

Banned Member
F135 is derived from the F119 not the F110. :)


You mean like the Harrier?


F-16 is mix of F100 and F110 engines... even newer aircraft are F110-129 or F100-229. The F-15 is P&W engines; only F110 powered F-15's are export.


Neither is the CFM-56 on the 737 any different to the GE F101 or F110?
And where did the F119 come from?

Yes, the F100 and the F110 are both used, the consequence of the "Great Engine War" :)

Harrier with no guns? I have never seen a field photo without 2× 30 mm (1.18 in) ADEN cannon pods under the fuselage

Cheers
 

cobzz

New Member
F-119 was developed from scratch. Some technology from the F-119 was placed inside the -229. Rather similar to the GE90 vs GP7000. That doesn't imply the GP7000 is early 1990's technology, or the GEnx is either.

Harrier with no guns? I have never seen a field photo without 2× 30 mm (1.18 in) ADEN cannon pods under the fuselage
Put an external pod on the F-35B. That's what the centreline pylon of for. :)
 

FutureTank

Banned Member
F-119 was developed from scratch. Some technology from the F-119 was placed inside the -229. Rather similar to the GE90 vs GP7000. That doesn't imply the GP7000 is early 1990's technology, or the GEnx is either.


Put an external pod on the F-35B. That's what the centreline pylon of for. :)
But the PW5000 was the ATF testbed engine back in the 1980s. It was selected for ATF in 1983 for both YF-22 and YF-23, and first was fired up in 1986. I had not been able to track down what served as the basis for its design though. The Air Force seems to think its going back to 1962 when they changed the engine designations to start with FXXX.

Yes, the gunpod. As I understand it (have only seem payload selection images) its just another option for the navy and USMC. With the RAF the Adens were pretty much fixtures as I understand. I had not really got into the payloads on the F-35 yet all that much, so I'm not sure what the thinking was behind not having an internal gun if they can have an external one. Can you enlighten me please?
 
A

Aussie Digger

Guest
Aussie Digger, I don't like being taken for a simpleton.
Then stop acting like one.

A new designation? Do you think that the aircraft being an F-35 had something to do with the engine being designated F135? I'm not even assuming, but certain that that designation was created as a business decision by the marketing team
However,
US military designations are not granted by the manufacturer and it has NOTHING to do with F-35 being the military title for the Lightning II. F-136? F-22/F-119? Where is the link here?

It is the follow-on designation for the F-119, as F-136 is for F-135.

There is no "design philosophies of the 2 engines".
Aha. Perhaps you could tell me why the F-119 is a turbofan engine that acts more like a turbojet and why the F-135/F-136 are turbofan engines and then come back to me and explain again why there is no “design philosophies of the 2 engines”.

Why can't you just say that the F135 has a larger fan! So what? That's not a different engine!
It does have a larger fan. And a larger compressor and an extra turbine stage the bypass ratio is different, the generated thrust is different, exhaust velocities are different and the physical dimension and layout of the engines are different, the health management systems are different.

But please, keep “showing” us all how they are the same…

This is extreme high altitude. So what, you are telling me is that an advanced strike fighter can't go supersonic at 31,000ft?!
I never said that. You have inferred, incorrectly once more. What I SAID was,

One is optimised for high altitude supersonic flight and the other is not
The F-119 is a turbofan design, but actually operates more like a turbojet with a low bypass ratio, good thrust and very high exhaust velocities.

The F-135/F-136 are turbofan designs, with a higher bypass ratio, excellent thrust but lower exhaust velocities.

The F-119 because of this and other design features is very good at flying supersonically and can do so for longer periods of time before engine burnout. They are particularly well designed for high speed, high altitude flying, but less so for lower speeds and lower altitudes.

The F-135/F-136 are also capable of supersonic flight and indeed such has already been demonstrated, however their design OPTIMISATION is predominantly for subsonic flight at lower levels. Where the F-35 will tend to operate, moreso than the F-22.

Perhaps you should try and read AND comprehend what I’m actually saying before spitting out rubbish about flying in commercial aircraft, as if that actually has some relevance to a discussion on supersonic fighters…

lease look again. It’s the same engine with a RR subassembly from Pegasus for directing vertical thrust.

  • The lift fan is not part of any engine so this statement is utter crap.


  • Neither the F-119/F-135/F-136 are the “same engine”.

I note you left out my 100-60=40 arithmetic from the quote.
Of course I did, it’s utter bollocks. You used 40% as a number to compare to 60 individual parts and somehow this equates to each engine having exactly 100 parts.

Utter ridiculousness.

Given they had to save weight and alter the performance somewhat,
Leaving aside the fevered ramblings in the rest of this paragraph, the F-135 and F-136 are both bigger in physical dimension AND heavier than the F-119.

They share the vast majority of overall physical parameters in order to comply with logistics and maintenance commonality specifications of the F-22. Probably to 90% if not more.
Prove it. Show me SOME evidence of the F-119 and F-135’s “majority of overall physical parameters”.

I beg to differ, but P&W are not probably the most successful jet engine manufacturer, just the one selected for the JSF program.
Aha. How many fighter engine manufacturers are their in the world? A handful?

F-135 – F-35A/B/C/D.
F-119 – F-22A.

F-100 – F-16 and F-15.

F-117 – C-17A Globemaster.

JT8D – 727/737.

JT9D – 747/767/A300/A310/DC-10

PW2000 – 757.

PW-4000 – A330

PW-4000-112 – B 777.


Right again I guess… L

P&W are attempting something that has never been done before? No, they designed an engine for a fighter. That's been done before.
Not like this it hasn’t. It’s been done since, by the F-136, but not before. Not with the balance of requirements v cost and efficiency expected.

efore you turn this into some sort of miracle, the F-16 was powered initially by the Pratt & Whitney JTF22 (F100) but was later changed to the General Electric F110.
More crap. GE F-110 is the ALTERNATE engine for the F-16 just like F-136 is the ALTERNATE engine for F-35. Neither engine is related, beside the fact that either can fit in and power and F-16 or F-15.

New-build F-16’s are being delivered with evolved variants of F-100 right now. As are F-15’s. Korea in fact has chosen both the F-100 AND the F-110 for it’s F-15K fighters, for some unknown reason.

The P&W greatness I fear is somewhat exaggerated.
Yeah. Being the primary engine supplier to the largest fighter type in the world (F-16) is obviously no great achievement…

Being selected as the primary fighter engine supplier to it’s replace isn’t worth bragging about either…

This is getting pathetic.

So how was it that innovations supposedly only available from 2002 were incorporated into a 1989 engine?
And you want me to stop treating you like a simpleton? How could an old engine be upgraded? Hmm. Gee. Ever been to car club rally? Ever been to the drag races? However do they manage to fit new, upgraded engine components to old engines?

The YF120-GE-100 (GE model GE37) [X – Experimental, Y - Service Test] was a rival to F119, and...you will love this..."The YF120 has 40 percent fewer components than the F110." : Yes the same GE F110 that powers the F-16/F-15 aircraft, and the one that the F-135 is derived from
The P&W marketing team are really earning their keep I think
I’ve had enough of this rubbish. GE makes the F-110. It also makes the F-404/F-414. In conjunction with Rolls Royce, it is designing and producing the F-136.

Neither the GE F136 nor the P&W F135 even have a manufacturer’s model number.
Hang on, at the start of your post, F-135 WAS the manufacturers numbers, remember?

being designated F135? I'm not even assuming, but certain that that designation was created as a business decision by the marketing team
Certain or not certain?

In terms of overall design the VSTOL capability of the B version is negligible.
Now I’m thinking you’re smoking something you shouldn’t. Have you SEEN the size of the lift fan needed to lift a 60,000lbs fighter, vertically into the air?

And here’s your own quote:

There will be three design variations of the aircraft based on the different missions of the Navy, Marines and Air Force.
Do you believe the quotes you are putting in your post or not?

It is same engine AD.
Different variants, same core. Check the bypass ratios, thrust generated and exhaust velocities if you don’t believe me. Very good guestimates are around… J

PLEASE give civilians some credence of having a brain.
[FONT=&quot]When it’s actually used, I will. [/FONT]
 

FutureTank

Banned Member
Do you know what AD, I would have to write a book to convince you.

You keep saying that I don't read what you say when you write in some hyperbolic code, but when I write 100%-40%=60% you choose to ignore that.

For the record, the engine Air Force codes are written without a dash, F135, not F-135. F - Turbofan http://www.designation-systems.net/usmilav/engines.html#_MILSTD1812_AirBreathing

Every, EVERY pilot in the World knows that the best engine in the world is the one that doesn't fail him or her when they are in the air. I hope you collect your bonus from P&W.

However, I am not going to reply to this for two reasons.
You lack the courtesy to at least quote me in full.
And you use insulting language.

If I was 100% wrong, nothing gives you the right to either.

Then stop acting like one.



US military designations are not granted by the manufacturer and it has NOTHING to do with F-35 being the military title for the Lightning II. F-136? F-22/F-119? Where is the link here?

It is the follow-on designation for the F-119, as F-136 is for F-135.



Aha. Perhaps you could tell me why the F-119 is a turbofan engine that acts more like a turbojet and why the F-135/F-136 are turbofan engines and then come back to me and explain again why there is no “design philosophies of the 2 engines”.



It does have a larger fan. And a larger compressor and an extra turbine stage the bypass ratio is different, the generated thrust is different, exhaust velocities are different and the physical dimension and layout of the engines are different, the health management systems are different.

But please, keep “showing” us all how they are the same…



I never said that. You have inferred, incorrectly once more. What I SAID was,



The F-119 is a turbofan design, but actually operates more like a turbojet with a low bypass ratio, good thrust and very high exhaust velocities.

The F-135/F-136 are turbofan designs, with a higher bypass ratio, excellent thrust but lower exhaust velocities.

The F-119 because of this and other design features is very good at flying supersonically and can do so for longer periods of time before engine burnout. They are particularly well designed for high speed, high altitude flying, but less so for lower speeds and lower altitudes.

The F-135/F-136 are also capable of supersonic flight and indeed such has already been demonstrated, however their design OPTIMISATION is predominantly for subsonic flight at lower levels. Where the F-35 will tend to operate, moreso than the F-22.

Perhaps you should try and read AND comprehend what I’m actually saying before spitting out rubbish about flying in commercial aircraft, as if that actually has some relevance to a discussion on supersonic fighters…




  • The lift fan is not part of any engine so this statement is utter crap.


  • Neither the F-119/F-135/F-136 are the “same engine”.



Of course I did, it’s utter bollocks. You used 40% as a number to compare to 60 individual parts and somehow this equates to each engine having exactly 100 parts.

Utter ridiculousness.



Leaving aside the fevered ramblings in the rest of this paragraph, the F-135 and F-136 are both bigger in physical dimension AND heavier than the F-119.



Prove it. Show me SOME evidence of the F-119 and F-135’s “majority of overall physical parameters”.



Aha. How many fighter engine manufacturers are their in the world? A handful?

F-135 – F-35A/B/C/D.
F-119 – F-22A.

F-100 – F-16 and F-15.

F-117 – C-17A Globemaster.

JT8D – 727/737.

JT9D – 747/767/A300/A310/DC-10

PW2000 – 757.

PW-4000 – A330

PW-4000-112 – B 777.


Right again I guess… L



Not like this it hasn’t. It’s been done since, by the F-136, but not before. Not with the balance of requirements v cost and efficiency expected.



More crap. GE F-110 is the ALTERNATE engine for the F-16 just like F-136 is the ALTERNATE engine for F-35. Neither engine is related, beside the fact that either can fit in and power and F-16 or F-15.

New-build F-16’s are being delivered with evolved variants of F-100 right now. As are F-15’s. Korea in fact has chosen both the F-100 AND the F-110 for it’s F-15K fighters, for some unknown reason.



Yeah. Being the primary engine supplier to the largest fighter type in the world (F-16) is obviously no great achievement…

Being selected as the primary fighter engine supplier to it’s replace isn’t worth bragging about either…

This is getting pathetic.



And you want me to stop treating you like a simpleton? How could an old engine be upgraded? Hmm. Gee. Ever been to car club rally? Ever been to the drag races? However do they manage to fit new, upgraded engine components to old engines?



I’ve had enough of this rubbish. GE makes the F-110. It also makes the F-404/F-414. In conjunction with Rolls Royce, it is designing and producing the F-136.



Hang on, at the start of your post, F-135 WAS the manufacturers numbers, remember?



Certain or not certain?



Now I’m thinking you’re smoking something you shouldn’t. Have you SEEN the size of the lift fan needed to lift a 60,000lbs fighter, vertically into the air?

And here’s your own quote:



Do you believe the quotes you are putting in your post or not?



Different variants, same core. Check the bypass ratios, thrust generated and exhaust velocities if you don’t believe me. Very good guestimates are around… J


[FONT=&quot]When it’s actually used, I will. [/FONT]
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
More crap. GE F-110 is the ALTERNATE engine for the F-16 just like F-136 is the ALTERNATE engine for F-35. Neither engine is related, beside the fact that either can fit in and power and F-16 or F-15.
Just to reinforce this for FutureTank, the contract requires the supply of alternate engine solutions. The US does it for redundancy as well as competitive purposes. USN does the same with some of its Major CAPEX.
 

FutureTank

Banned Member
Just to reinforce this for FutureTank, the contract requires the supply of alternate engine solutions. The US does it for redundancy as well as competitive purposes. USN does the same with some of its Major CAPEX.
It seems to me this started when the US Air Force and the Navy were unhappy with the engines they got in the F-14s and F-16s. Need to verify that though if the practice of requesting alternate engines is older. That little episode nearly bankrupted P&W.
 

Feanor

Super Moderator
Staff member
FutureTank you point to the BoM... but are the BoM for the two engines identical?
 

FutureTank

Banned Member
FutureTank you point to the BoM... but are the BoM for the two engines identical?
Of course they are not identical. That's how they find out the difference in how many parts go in each engine. The head of project doesn't sit there counting parts. They just get a report. I have ran these reports before. Actually you just get a summary report. Its standard practice in project management accounting where engineering is concerned.

What I find amazing is that they reduced the number of parts by the same number as the earlier GE engine :) That is either a huge coincidence or a bit of marketing plagiarism :)
 

cobzz

New Member
What's the idea here? P&W, GE & RR are in on a conspiracy to make the engines more expensive than they should be for "30 year old technology"? By the way, the turbine in the F-135 needs to be abled to provide 29,000 shaft horsepower to the lift fan. Subtle differences? Wonder why they got the Collier Trophy.

Maybe subtle differences in the same way the GE F101 on the BONE is the same as a CFM-56 on the 737; after all, they are components and they're both optimised for subsonic cruise at flight level 300... right? I guess the C-5M is another conspiracy fitting CF6-80C2 where the TF39 is the same thing! 40 year old technology.

I think they removed the cannon to shave off some extra weight, and add fuel capacity. Not sure though. Either way, the cannon was external on the harrier; so it's really nothing new.

Every, EVERY pilot in the World knows that the best engine in the world is the one that doesn't fail him or her when they are in the air. I hope you collect your bonus from P&W.
Well engines are not sold on the basis that they 'don't fail when they are in the air'. They are sold on performance, risk, and cost. P&W is the most successful in military aviation; clearly; thus in the past are likely the best on the three factors outlined above.

Why are you then saying the USAF was unhappy with the F100, even though it usually doesn't "fail when in the air"? Contradictatory. BTW, F110-129 has had more engine failures than F100-229. :)

Also, 100 - 40 = 60%.... doesn't mean it has 60% in common with F119. EVERY single part could be different. For example, if a car has 100 parts and a boat has 80 parts doesn't mean 20% in common...
 
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FutureTank

Banned Member
What's the idea here? P&W, GE & RR are in on a conspiracy to make the engines more expensive than they should be for "30 year old technology"? By the way, the turbine in the F-135 needs to be abled to provide 29,000 shaft horsepower to the lift fan. Subtle differences? Wonder why they got the Collier Trophy.
I'm not saying its a conspiracy, but I would like to know how an engine first fired up in 1986 goes into production 20 years later as if it was some miracle, costing what seems to me to be exorbitant amount of money.
I must admit I don't know what its initial 1986 performance was, but here is an interesting read http://www.flightglobal.com/pdfarchive/view/1986/1986%20-%202974.html, including on the P&W's superiority as an engine manufacturer.

Maybe subtle differences in the same way the GE F101 on the BONE is the same as a CFM-56 on the 737; after all, they are components and they're both optimised for subsonic cruise at flight level 300... right? I guess the C-5M is another conspiracy fitting CF6-80C2 where the TF39 is the same thing! 40 year old technology.
And? I hadn't done research on these, so can't really comment.

I think they removed the cannon to shave off some extra weight, and add fuel capacity. Not sure though. Either way, the cannon was external on the harrier; so it's really nothing new.
Yes, I think you are right, but the pod doesn't look very 'stealthy' to me. It looks like that thing pastry chefs use to squeeze cream :) If I was making it 'stealthy', I think I would use a boat/shield shape, but that's me. The Harrier was never designed to be 'stealthy' :)

Well engines are not sold on the basis that they 'don't fail when they are in the air'. They are sold on performance, risk, and cost. P&W is the most successful in military aviation; clearly; thus in the past are likely the best on the three factors outlined above.
I think there are different criteria for evaluating success in engine design. I was actually quoting a pilot. I don't think its fair to say P&W are the most successful. Other companies make engines for other aircraft. If it flies, its good :)

Why are you then saying the USAF was unhappy with the F100, even though it usually doesn't "fail when in the air"? Contradictatory. BTW, F110-129 has had more engine failures than F100-229. :)
Yes, the Air Force was unhappy. GE even uses that to support its case for being the alternative engine supplier http://www.fighterengineteam.com/about_case.html
You can read about it here Drewes, Robert W., The Great Engine War, National Defense University Press, Washington D.C., 1987., but this came from Lt Col Clyde M. Woltman's report after he was embedded with the P&W.
In 1984 Pratt & Whitney experienced a warning call that came to be known as the “Great Engine War”. Researchers from Harvard University School of Business conducted a study titled The Great Engine War, which led to the commercial publication of the same title . This thesis chronicles the events and lessons learned leading to and following Pratt & Whitney’s unprecedented loss of a single-source government contract award.
www.ndu.edu/sdcfp/reports/P&W%20Final%20Report.doc I guess that must have been the first time competitive alternative engine became a contractual requirement.

Also, 100 - 40 = 60%.... doesn't mean it has 60% in common with F119. EVERY single part could be different. For example, if a car has 100 parts and a boat has 80 parts doesn't mean 20% in common...
If it doesn't meant that, why are P&W saying it? Clearly they are comparing two engines. If they are different engines, why compare them? Clearly two different engines will have different number of parts just like two four door sedan Fords and Toyotas will have different number of parts. But, in this case we are comparing two engines made by same company, with one being a derivative. This is clear from the actual renaming of the F119 (actually JSF119-611) into the F135. The Air Force just went and renamed it. The actual changes, though reducing the number of parts were not that significant. Ordinarily, as I understand it, a new F number would not be allocated, but in this case they did. Maybe the general preferred to say F135 in the F-35, I don't know. Maybe it looks better on the aircraft parts list :)
I am not an engineer. I can only go on the information available to me. However, the people that write for this site http://machinedesign.com/article/the-joint-strike-fighter-a-plane-for-all-reasons-0307, are, and they also say
Powering all JSFs is a single JSF119-611 jet engine from Pratt & Whitney, an updated version of the afterburning turbofan engine used in the F-22 Raptor. The low-bypassratio engine has been updated with a new fan and lowpressure turbine, taking the engine from the 35,000-lb class to the 40,000-lb class. It has also recently been renamed the F135 engine. To ensure the military doesn't rely on a single engine supplier, and to maintain the nation's jet-engine industrial base, Congress insisted on an "Alternate Engine." GE, Allison, and Rolls-Royce are refining their F-120 engine to meet this requirement.
By the way, there is an excellent view of the lift fan there, and some more gems, like "The JSF cockpit's two large color displays were original to the C-130J Hercules", though this changed to one Panoramic Cockpit Display (PCD) in the production model.
 
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A

Aussie Digger

Guest
Do you know what AD, I would have to write a book to convince you.

You keep saying that I don't read what you say when you write in some hyperbolic code, but when I write 100%-40%=60% you choose to ignore that.
Check your original post. You weren't referring to percentages throughout your so-called "equation".


For the record, the engine Air Force codes are written without a dash, F135, not F-135. F - Turbofan http://www.designation-systems.net/usmilav/engines.html#_MILSTD1812_AirBreathing
So you are aware that military platforms have military proscribed designations? Makes me wonder about that rubbish you posted earlier about F-135 being named after F-35...

Every, EVERY pilot in the World knows that the best engine in the world is the one that doesn't fail him or her when they are in the air. I hope you collect your bonus from P&W.
Ask the US DoD what the safest fighter aircraft (based on number of crashes as an overall percentage) in the US fleet is. You'll find it's the F-16 powered by none other than P&W.

If I was 100% wrong, nothing gives you the right to either.

You weren't 100% wrong. Just plenty wrong. About this and quite a few other things.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
By the way, there is an excellent view of the lift fan there, and some more gems, like "The JSF cockpit's two large color displays were original to the C-130J Hercules", though this changed to one Panoramic Cockpit Display (PCD) in the production model.
Why's it a gem? Up until the C17 in RAAF colours, the Herc J was by far the most sophisticated cockpit system in service. In fact it was regarded as the leading electronic systems platform bar C17 and the A380. (and would still be in the top 3 per se)

You seem to be oblivious to the fact that a number of the JSF systems were muled by other platforms and considered on the basis of capability.

In fact no other platform in the history of aircraft development has gone through the same test and eval process of the JSF - period. Trying to draw comparison straws to prev generation developments is a nonsense - and is the very reason why GAO and POGO got things wrong.

Again, at the briefing at Avalon, the builder has been vindicated and the GAO made to look a little amateurish in their initial assessment. On time, (actually ahead of time) and with improvements in a number of flight models that weren't anticipated.

This jousting for attention is becoming tiresome, it's akin to comparing the building of the Manly Ferry with HSV-2 and ignoring not only tech developments, but build developments, integration developments and the fact that the operational concept for this aircraft family has never been persued at a comtemp level.
 

Haavarla

Active Member
cobzz;170256]What's the idea here? P&W, GE & RR are in on a conspiracy to make the engines more expensive than they should be for "30 year old technology"? By the way, the turbine in the F-135 needs to be abled to provide 29,000 shaft horsepower to the lift fan. Subtle differences? Wonder why they got the Collier Trophy.

Maybe subtle differences in the same way the GE F101 on the BONE is the same as a CFM-56 on the 737; after all, they are components and they're both optimised for subsonic cruise at flight level 300... right? I guess the C-5M is another conspiracy fitting CF6-80C2 where the TF39 is the same thing! 40 year old technology.

Well engines are not sold on the basis that they 'don't fail when they are in the air'. They are sold on performance, risk, and cost. P&W is the most successful in military aviation; clearly; thus in the past are likely the best on the three factors outlined above.

P&W do produce fantasic engines, but it is difficult and complicated to measure them against the AL-31F series.

They probebly score more than the AL-31F given at 1000 hours with a full-life span of 3000 hours.

And in the thrust regime too..

But there are different design parameters between western and Soviet/Russian built aviation engines.

The AL-31F has a reputation for having a tremendous tolerance to severely disturbed air flow. In the twin-engined Flanker, the engines are interchangeable between left and right.

They are sett to operate at much harsher clima than many of the vestern counterparts.

The AL-31F can operate in a wide range of reliably altitudes and flight speeds. The engine works reliably in conditions of deep surge of the air intake with M=2 as well as in flat, straight and inverted spins. The engine ensures unique aircraft maneuverability including super dynamic aerobatics in negative speeds up to 200 km/h.

The AL-31F provides high gas dynamic stability and strength which maintain engine reliable performance in extreme condition of inlet distortion.
The AL-31F can be manufactured both in standard and tropic version.


I wouldn go claiming P&W for the WORLD best millitary aviation manufactors..

How about the best WESTERN best millitary aviation manufactor?
 

FutureTank

Banned Member
Check your original post. You weren't referring to percentages throughout your so-called "equation".

So you are aware that military platforms have military proscribed designations? Makes me wonder about that rubbish you posted earlier about F-135 being named after F-35...

Ask the US DoD what the safest fighter aircraft (based on number of crashes as an overall percentage) in the US fleet is. You'll find it's the F-16 powered by none other than P&W.

You weren't 100% wrong. Just plenty wrong. About this and quite a few other things.
You MUST BE JOKING!!!! BOTH P&W and GE refer to the percentage of parts. I repeated it in the original post. To even suggest that I would launch into a discussion about aircraft engines on the premise it had 100 parts even as an example is absolutely ludicrous. Just using a different clamping system can eliminate dozens of parts. Removal of one component to a different location on the engine can result in elimination of half its fasteners. Change of one controller for another can eliminate many of its surface mounted components that are also on the BOM. With wiring changes I bet I just covered half of those 40%. Most of the changes to improve performance would have been with like parts, and would not have resulted in the BOM reduction overall. Engines don't have that many sub-assemblies , even advance combat aircraft engines. I recommend the Rolls-Royce book The Jet Engine which is downloadable online if you look. Its enough information for a layman like me.

The change in military designation came from a USMC LTC who was at the time embedded with the P&W and now works for them. I suppose he would know since he gives the exact date when that designation was changed. He says the nomenclature changed, not the engine. Actual engineering changes are not reflected in the Engine Program name, which is what the F135 refers to, but in the project engineering reviews and spec revision notes.

And ask the US Air Force why they required a GE engine for the F-16s, and why the P&W engineers would go to bases to Air Force heads of engineering meetings, they had a lawyer attending in the 1980s :)

To me it looks like you are just reading out of the P&W marketing material.

You think I'm 100% wrong, you are welcome to your opinion. I am not bothered by it.

I checked the information before posting here. I admit I am not an engineer, and I may have made one or two mistakes related to the engineering issues, but the question I raised is not an engineering one really. Its more to do with the project management side of things.

To me it looks like the project was dragged out, and the price was inflated because after this program there will be only two significant combat aircraft flying in the USA, and after that who knows. It seems to me the project is just being 'milked'. That engine, and in fact the whole F-35, should have been in production in 2004-5 and with even less of a price tag because most of the design and development had already been completed before 1994 in legacy projects. The next six years were dragged out by the QDR, and since 2002 its been DoD-driven scope creep carefully managed by LH&Co.

If you don't like this conclusion, that's your choice. However, what with a loss of 2 trillion dollars in the US economy, I just think that the generals may have shot themselves in the foot with this program, and that is why they were/are rushing the F-35 into production. With the Democrats and the GFC they are going to have a lot of problems keeping the production numbers and that means, as you pointed out, an even more expensive aircraft. In the end it turned out to be all about politics and economy, and not technology.

Who would have guessed...
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
I wouldn go claiming P&W for the WORLD best millitary aviation manufactors..

How about the best WESTERN best millitary aviation manufactor?
Mid last year the USG determined that the F-16 had the highest availability and safety rate of any single engined jet fighter in the world - based against total production. Guess which engine dominates F-16 production?

up time, turn around, catastrophic failures etc measured against total production.
 
A

Aussie Digger

Guest
You MUST BE JOKING!!!! BOTH P&W and GE refer to the percentage of parts.
Do you HONESTLY think both engines DON'T have the same requirement to meet? Do you not think the manufacturers are in competition?

Both have stated a 40% reduction in part numbers from previous engines. I agree. You somehow equated this to mean "100 parts" and I've already pointed this out in previous quotes of YOUR earlier statements.

I repeated it in the original post. To even suggest that I would launch into a discussion about aircraft engines on the premise it had 100 parts even as an example is absolutely ludicrous.
Then be more careful in what you type and what you comprehend in future before posting, because that IS what you posted.

And ask the US Air Force why they required a GE engine for the F-16s, and why the P&W engineers would go to bases to Air Force heads of engineering meetings, they had a lawyer attending in the 1980s :)

To me it looks like you are just reading out of the P&W marketing material.
You think I'm 100% wrong, you are welcome to your opinion. I am not bothered by it.
Again with the percentages. No wonder you were never an engineer...

I checked the information before posting here. I admit I am not an engineer, and I may have made one or two mistakes related to the engineering issues, but the question I raised is not an engineering one really. Its more to do with the project management side of things.
Keep back pedalling brother. It does a debate the world of good...

To me it looks like the project was dragged out, and the price was inflated because after this program there will be only two significant combat aircraft flying in the USA, and after that who knows. It seems to me the project is just being 'milked'. That engine, and in fact the whole F-35, should have been in production in 2004-5 and with even less of a price tag because most of the design and development had already been completed before 1994 in legacy projects. The next six years were dragged out by the QDR, and since 2002 its been DoD-driven scope creep carefully managed by LH&Co.
Don't forget the multiple fan blade failures on F135 test engines in 2007 along with the lift fan shaft snapping...

I'm sure these issues didn't contribute any significant delay...
 
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