ADMK2You are proven wrong so many times. Power on the bench says nothing about its “quality” and the F135 is running very hot already. The F-35B is in need of military or cold thrust at first. No severe issue for the F-35A and C at first and by that it got less notice but a lot of hope PW will solve it some day by still unknown cost demands. $2B are peanuts compared to the F-35 program other cost over-runs within. Maybe you get a second thought why GE is investing own money despite a late start. To select between producer gives power to the customer. He can choose by performance or by price. 😎
$2b is peanuts is it? God, you must have some coin…
I seem to recall that the the LRIP IV contract was only $3.7b and yet $2b is peanuts? 124 aircraft have been cut from production prior to 2015 from the program already because there’s no money but they can afford $2b more on development of an engine that cannot use any more thrust than it’s competitor, one that has already reached ISR and which will also require an enormously expensive and duplicated training and logistics support package should it actually be purchased…
I don’t personally care which engine is bought, but paying for two engines which won’t offer any significant difference between them, is simply wasteful in the extreme. No-one can afford it anymore. Not even the USA.
ADMK2The F136 is not coming at the expense of F-35 airframes for it’s customers like the F110 before.
Some people will never learn that the lack of competition will never bring the most cost effective fighter engine in general.
The idea of the more capable F136 was rejected, because it was in need of a longer development time compared to the less demanding F135. The development of the F-35 takes much longer than planned and time is no longer a critical issue, when it comes to the engine.
The F135 and F136 do not differ in production cost. The smaller part is the development cost, because both engines are based on the same technology developed by the states institutions. The F135 is pushed to its design limits already, when the F136 has still some healthy growth ahead.
The customers will decide, which is the best “10 mio. $” engine for their F-35s from 2015. 😎
The F135 is hardly ‘pushed to it’s limit’ at 43,000lbs on the test bench.
P&W have already demonstrated the F135’s capability to exceed their thrust requirement by 28% in it’s current configuration…
http://www.codeonemagazine.com/news_item.html?item_id=217
Next…
ADMK2Sounds like similar arguements made during the development of the GE F110. Which, was designed to compete with the P&W F100 Series for the F-16.:rolleyes:
The difference being that I’m not aware of the F110 coming at the expense of F-16 airframes for it’s customers though.
That is very much likely to be the case with F136 funding…
ADMK2Nor, greater performance……:eek:
BTW The current GE F136 is going to make 5% more thrust than the P&W F135 from the start. (i.e. 43,000 vs 45,000 lbs +):diablo:
Again, so what? Neither engine can exploit any existing thrust advantage with the existing LOAN exhaust nozzle, which is being used for BOTH engines. It has a standard fixed area and this is what restricts the F135/F136 to about 40,000lbs of thrust. Both engines have developed more in earlier iterations.
The F136 may be slightly more economical with this “standard” thrust level given it may produce 5% more potential thrust but is that a good tradeoff for the numerous airframes that AREN’T going to be bought so that the F136 can be fully developed and potentially bought later?
Not hardly…
Any thrust increases in the F136 will be met by the P&W engine. They’ve earlier demonstrated far more thrust then they’ve ended up producing for the F135 and they have development programs of their own for their engine just as GE/RR have for the F136.
The interesting thing though is that both USN and USMC have already stated publicly they will only be buying one engine type and they will buy a lot of F135’s before the F136 is ready even if it is fully developed…
ADMK2Other than to
a) Promote innovation in engine technology.
b) Keep Pratt and Whitney honest on pricing.
c) Keep some airframes flying in the case of problems with the F-35.Left alone as a monopoly, Pratt and Whitney has no incentive to deliver a reliable product at reasonable price.
Er, besides company profits, good will with the customer and a good reputation amongst the market place you mean?
I often wonder why that is so important in the US for the JSF to have 2 separate engines, but nowhere else in the world and in no other modern development program is it considered so necessary?
Typhoon – 1 engine supplier.
Rafale – 1 engine supplier.
Gripen – 1 engine supplier.
SU-35 Sukhoi – 1 engine supplier.
JF-17 – 1 engine supplier. (Perhaps a change to a domestic engine supplier later in program, however only one current and one planned).
J-10 – 1 current engine supplier. (Perhaps a change to a domestic engine supplier later in program, however only one current and one planned).
F-22A – 1 engine supplier.
F/A-18E/F Super Hornet – 1 engine supplier.
Not one of these aircraft programs has a second domestically manufactured engine supplier. In each case they make up a significant part of, if not the total air combat capability operated by their respective Countries and many of them are single engined fighters, yet they don’t need a second engine source. What makes the JSF so different besides pork-barrel politics?
Is Pratt and Whitney really such an unreliable engine provider?
As I said earlier, why should a second engine be funded at the expense of F-35 airframes? Airframe numbers are being cut due to a lack in funding, which is driving up the overall cost and entering into a dangerous circle, yet apparently they can afford billions to buy a second engine that offers nothing more than a different engine of the same general specifications as it’s competitor?
It is likely to cost $1.6B or MORE (CRS states it could cost more than $2b) to finish the F136 and there are no guarantees it will even be bought, let alone used in significant enough numbers by the Country that is actually paying to develop it – the USA.
I don’t get it at all I’m afraid.
ADMK2The problem for RAN as far as a Carrier replacement went was at that the same time as the Carrier needed replacing RAN also needed a new fleet of ASW helicopters (S-70B9’s) an additional 2 FFG Frigates and a new submarine fleet and a replacement for the River class Destroyer Escorts.
RAN ended up getting – 16x S-70B9 Seahawks, 8x ANZAC Class FFH’s, 6x Adelaide Class FFG’s and 6x Collins Class submarines. In addition RAAF got extra P-3C Orions in the 1975-1980 era, that probably wouldn’t have occurred if RAN got her carrier.
On top of this the F-111, Oberon class subs, FFG’s, P-3C Orions and F/A-18 all had the Harpoon anti-ship missile integrated and brought into ADF service a significantly increased maritime strike capability.
It is likely that virtually all of that (bar the initial 4x FFG’s) would have had to be sacrificed in order to acquire the carrier and a new airwing as there was precious little money for defence in those (and these unfortunately) days…
Personally I think the ADF actually profitted by not getting a carrier.
ADMK2I don’t think India has any plans to export the Tejas, HAL will struggle to even meet the IAF & IN demands. So flying it to Europe will be a waste of time and money. A practical problem is the current Tejas version do not have a IFR probe so it will be impossible for it to get to Europe in its own power.
It can’t transit through a number of different airfields, refuelling on the way and providing rest for the crew/s, like every other aircraft in the world, does?
:confused:
ADMK2Exactly. The benefits are huge and the cost is comparatively trivial. Gates’ justification for canceling the F136 is that it the F-35 development budget can’t afford it. The remaining cost of F136 development is something like $300 million. If the F-35 is that close to the edge, then there’s no reason to continue; that’s a tiny fraction of the total cost overruns the program has incurred so far.
The GAO stated that they believed the F136 would require something in the order of $1.6b to complete development…
ADMK2It really doesn’t make sense to cancel the F136. The technology could lead to more advanced civilian turbofans. It will also keep next-gen fighter engine technology know-how active in two companies!
GE already has next gen engine contracts with the developments that the F414 is benefitting from (EPE and EDE engines, Advent etc).
F136 is pork-barrelling at it’s absolute finest. It’s a waste of money in these financially strapped times. It doesn’t matter how much power the F136 delivers compared to the F135 because both engines are limited to a specific maximum thrust by the LO exhaust nozzle fitted to the F-35.
The F136 could make double the power of the F-135, but would never be able to exploit this advantage. Of course it would probably be a far more reliable and economical engine if it COULD make that much power, but only used 50% of it’s max, but power wise it doesn’t make any difference how much the F135 or F136 because they are both limited by the nozzle design…
ADMK2More F-35B Delays, Software Schedule At Risk
Why I’m just SHOCKED that there’s a problem with the F135. I had been ASSURED that it was PERFECT and there there was ABSOLUTELY NO NEED for the F136.
There isn’t a need for the F136. Not at the cost of airframes to develop it anyway.
Screech isn’t a major issue. It is something that pops up in flight testing from time to time because apparently it is quite difficult to model supersonic exhaust flows from jet engines. The “screech” is an unstable combustion in the augmentor (afterburner) and simply requires a bit of fine tuning of fuel flows etc to fix.
No biggie.
ADMK2You’ll note that this problem is related solely to the B model. The A/C models don’t share this issue.
Screech is a problem with unstable combustion in the augmentor. As all three models share the same augmentor…
It is a relatively easy problem to address from all accounts, given that “tuning” (fuel metering, software changes) the engine is the main way to resolve the issue and most new engines suffer the problem to some degree.
It isn’t a “game changer”…
ADMK2Neither does mine. 🙂
I actually believe those who actually fly the thing can be trusted to speak about it. But I see a big difference in who does that. An Italian AF jockey can easily say “hey, this aircraft sucks because it’s lazy and slow” if he sees fit. Mr.Beesley can’t.
What about an RAF pilot?
🙂
ADMK2Is that a Litening pod I see being carried on the Tejas?
ADMK2It isn’t that simple. If I look at my working contract, I can see several clausules aimed as deterrence against me providing sensitive information to public or competition once I should quit. They are both of prohibitive (e.g. penalties) and motivative nature (extra “loyalty” bonuses). Note that I am not in Mr.Beesley’s position and the information I got would harm my company not even close compared to what damage to Lockheed’s PR/sales Mr.Beesley could theoretically cause.
I think that this man’s silence and obeyance regarding what he says publicly or privately costs the company a small fortune and this will remain so for quite a time to come. It would be a gross omission from the side of the employer if they hadn’t thought about this in every detail and simply let their employees or ex-employees with access to sensitive information go out and spill the beans publicly …
All true enough, but remains mere speculation designed to support your assertion that he doesn’t “tell the truth”.
Keeping his job is not a motivation for this person. As I’ve said he’ll be retired completely within the next 6 months and whether he has any formal condition to “remain quiet” or not, still doesn’t prove that what he has to say about the aircraft is invalid.
I find it a very curious point that many people believe those who actually fly the thing can’t be trusted to speak about it, but yet those who haven’t flown anything comparable in years and even then it was only on as a backseater “media ride” and have no visibility inside the program whatsoever are considered believable by so many.
Does not seem logical at all to me. Lucky my career doesn’t ride on these things, eh?
ADMK2The chief test pilot(of both the F-22 and F-35 programs, that can compare the 2 types based on first hand knowledge), being one of the key pilots in question. I know the typical response is that he’s just a shill for LM, and wouldn’t want to risk his job. Methinks, Mr. Beesley wouldn’t have much trouble finding a job at any of a number of other aviation firms, with his background and experience.:eek:
Mr Beesley is retiring this year. Retaining his job surely isn’t high on his priorities…
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