Another fun slide:

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This slide, combined with the previous one showing the 380+ F-35s that will already have been delivered by 2018 illustrates the value of the infamous “concurrency” built into the program.

It certainly hasn’t been free of costs, but it means that in roughly 3 years when the software arrives the operators will already have taken delivery of a substantial number of airframes and will be taking delivery of another 150+ every single year. 🙂

The F-35 will go from a quite limited capability at IOC this summer, one squadron with only a few weapons, to a significant real world capability in only a few years.

Hopsy, you are on the ignorelist so I and many others dont read 99% of what you post. But thanks for the information.

If you prefer to live in a fanboy echo chamber then you can hardly complain about not knowing what is going on.

So… they will deliver a jet to the customers in 2012-2021. But it will be, surprise, unfinished and only deliver the promised capability once the operators buy a new engine. I have never heard of anything like this for western fighters.

Try the F-14.

Delivery schedule:

Come to think of it, why would any customer/partner ask for deliveries before 2022? By waiting just a few years they will get a jet with lower operational costs and higher performance.

Because people need/want their aircraft earlier. Don’t forget there are substantial costs associated with keeping older airframes operational past their intended service lives as well.

Remember the scale of the F-35 program. By the time 2018 rolls around there are scheduled to have been 386 F-35s delivered. (see slide below) Per your chart there will be another 170-180 additional F-35s delivered in each of 2019, 2020, and 2021… meaning by 2021 there will be ~900 F-35s delivered. 2022 would see that number rise to ~1100. That is a huge number of jets, significantly more than other recent fighter programs have delivered.

On the other hand, that is only 1/4 – 1/3rd of the anticipated F-35 production run meaning a new engine if delivered in the 2023-2025 time frame would still see a huge production run, certainly enough to justify the investment given the anticipated performance improvements. (and there is a 0% chance the various buyers would be willing to wait another 10 years for the first 1,000+ F-35s, and so the F135 is certainly necessary)

[ATTACH=CONFIG]236611[/ATTACH]

I think at this stage it can be done without tradeoff. The F135 engine is still new so there is likely room for some improvement without sacrifices.

From two pages ago…

Does anyone read this thread?

I haven’t seen this discussed here yet:

http://www.janes.com/article/50010/pentagon-to-build-new-variable-cycle-engine-for-f-35-and-other-aircraft

Pentagon to build new variable-cycle engine for F-35 and other aircraft

Key Points

The Pentagon’s new sixth-generation engine will be built for the F-35 and several other aircraft
The new engine would be 35% more fuel efficient than existing engines, extending the range of US aircraft significantly

The Pentagon’s developmental sixth-generation jet engine featuring greater fuel efficiency and thrust than existing military engines is initially being built for the Lockheed Martin F-35 Lightning II Joint Strike Fighter (JSF), a senior agency official said on 17 March.

“There are a number of threshold platforms,” Alan Shaffer, the principal deputy assistant secretary of defense, research, and engineering, told IHS Jane’s at the Precision Strike Association’s annual conference in Springfield, Virginia. “[This is] the one that we’re going to build it around because we’ll have the extra orange airplanes is JSF,” he added, referring to test aircraft.

…

Shaffer said the Pentagon plans to “develop engines with two vendors, and by 2019 or maybe 2020 have the capability to enter directly into [engineering and manufacturing development]”.

…

Shaffer said the DoD is aiming for a 35% improvement in fuel consumption efficiency over the fifth-generation engines with AETP. He said that this metric is largely aimed at providing greater range to its aircraft as the US turns its attention to the vastness of the Pacific Ocean.

Comment

It is widely expected that General Electric (GE) Aviation and Pratt and Whitney (P&W) will continue to be the two major players in the Pentagon’s propulsion technology push. GE Aviation’s projected timeline for developing its variable-cycle design to completion coincides well with the DoD’s plans. Company officials have said that their engine could be production-ready in the 2022-2024 timeframe. The have acknowledged spending upwards of USD1 billion on the effort in the decade since they offered the variable-cycle F120 to the Pentagon for the F-22 Raptor. They have claimed that variable-cycle technology alone cannot achieve the 35% fuel-burn improvement desired by the DoD. To achieve that metric, GE aviation has invested in ceramic matrix composites for the engine’s hot section, advanced aero designs in the compressor, and lightweight 3d-printed components, a list of components they claim is unique to GE Aviation’s design.

The article goes on to say that PW is working on upgrades to the F135 engine toward the same end goal, which they claim will be lower cost and risk.

This article, unless just completely wrong, makes it a virtual certainty that we will see F-35s with 6th generation engines starting in the mid-2020s, relatively early in its total production run. (meaning in retrospect the original F135 is likely to appear as almost an interim engine) Obviously there still isn’t an official program to put these engines into production, but I can’t imagine the Pentagon nor anyone else passing up on the opportunity to take advantage of the improved performance such an engine would offer, especially if the engine was already flying in the F-35 in prototype form.

The Jane’s article doesn’t say this, but other sources have also gone on the record as saying in addition to the increased fuel efficiency the new engines will also increase thrust, offer increased cooling, improve transonic and supersonic performance, and reduce IR signature.

The fuel savings alone would make such an engine an almost revolutionary leap forward. Not only would the F-35 see its range/endurance increased by a full third without any drag penalty, it would also likely save operators a huge amount of money. Suddenly F-35s would burn fuel like F-16s…

I’m afraid the analogy with the F-15SE is a rather crude approach since both the Su-35 and Pakfa feature BWB design which increases internal volume available for fuel whilst the eagle family has a separate conventional fuselage, hence its dependency on CWB and drop tanks to achieve a decent range.

Volume is volume, whether in a conformal bay or within the body of an aircraft. If the PAK FA can carry four Kh-58UShK missiles internally then it has some large bays.

The point of this is that Andraxxus has been arguing that the PAK FA has somehow found space to accommodate its sizable internal bays while maintaining the internal volume and fuel load of the Su-27. There simply isn’t nearly that much empty space in a modern fighter.

Further he is also trying to argue that internal bays, the doors of which are flush with the main fuselage of the aircraft and thus whose entire volume is inside the fuselage don’t count as “holes.” :confused:

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T-50’s internal weapon bays can accommodate four Phoenix-class missiles. Quite impressive.

Also, while the T-50 may be more aerodynamically efficient, its engines are more optimized for supercruise, which would likely mean higher subsonic SFC. Probably explains why it has comparable subsonic range to the Su-27 despite carrying more fuel. On the other hand, its supersonic range is twice as far.

To get an idea of just how much fuel you would have to trade away to hold four such missiles while retaining the same overall internal volume… consider that the F-15SE used its conformal fuel tanks(each of which hold 750gal/2,840L of fuel) as weapons bays.

The CWBs are actually able to retain some fuel while holding two weapons each, but I don’t think that would be the case with the larger Russia missiles we are talking about.

http://www.flightglobal.com/blogs/the-dewline/2009/03/f-15-silent-eagle-media-briefi/

Rough estimate is that converting the fuel tanks to weapons bays costs the F-15SE around 3,000-4,000kg of fuel. The PAK FA would need probably twice that volume to accommodate its internal bays. There is no way it has an internal volume equal to or less than an Su-35.

Dude, the T-50 has more fuel than the Su-27. We don’t know how its fuel compares to the Su-35. Compared to the Su-27, the T-50 does not have a dorsal airbrake, while also having greater wing area, so those are two potential sources of additional fuel volume.

Here is his original claim:

In essence, Su-35 is just a revised Su-27. PAK-FA on the other hand is a true clean sheet design. Its smaller in dimensions, and I don’t think T-50 has grater total internal volume than Su-35. It simply uses available volume better. No suprise it weights less than Su-35.

I’ve said total internal volume; If you can’t understand what I am saying, save your “stupid” smiley to yourself. For example, if you make elevators hollow and put additional fuel there, you will increase fuel capacity but total volume the aircraft occupies stay same. Similar example with MiG-29 to MiG-29M, additional fuselage tanks, (not talking about the ones replacing FOD inlets) improve fuel volume. PAK-FA, designed 40 years later, possibly uses way more of its volume for fuel capacity, and wastes way less, and again, I DO believe PAK-FA will turn out to have LESS total volume than Su-27/35.

Just so we are clear. You think there is sufficient -empty- internal space in a Su-35 that the PAK FA could incorporate its four internal weapons bays, plus its additional avionics, all without increasing its volume over that of the Su-35?

:stupid: :stupid: :stupid:

Why don’t you point out for us the wasted space you would reclaim:

Don’t forget…

The total fuel capacity is 14,350l. In order to increase the unrefuelled range and endurance compared to earlier models the Su-35 incorporates additional tailfin and fin-root tanks. The fuel tanks are of aluminium lithium construction and are located in the wings, fuselage and in the square-tip twin tailfins.

http://www.airforce-technology.com/projects/su-35/

Just so you know how much space you are looking for, remember you want to fit four of these:

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and a couple of these:

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I really do enjoy some of the technobabble you regurgitate onto this board, but come on now, think.

Eem.. then what was this line of yours all about?

Hense my reply..

Edit:
what do you propose.. LM wold make the FB-22, 25% larger(F-18=>SH) and call it an Stealth striker?

Do you see my point! The Penalties of the chosen F-22 design would still follow it.. as my and Peregrinefalcon post above suggests.

IMO, what it all come down to is this:

When you first decide to which design you will start with, you do not have much option to change course towards the end product.

The history of the Flanker developments is a perfect example of this. They had to go the long painfull road and redesign it towards the end product you see today.

The point of the example I made, completely lost on you it seems, is that optimizing a design to improve performance in one area almost invariably requires tradeoffs that negatively impact other performance areas.

The point of my FB-22 example was to say that adding fuel and carrying capacity would require increasing the aircraft’s internal volume. This in turn would lead to greater weight and drag that would degrade its kinematic capabilities.

It isn’t hard to imagine a FB-22 with greater range and carrying capacity. Imagining one with greater range, carrying capacity, reduced empty weight, increased speed, improved maneuverability is almost impossible.

Similar design tradeoffs appear in engines. An engine optimized for strong supercruise performance (as is the case for the F119) will suffer a penalty in fuel efficiency, reducing range and endurance. (as is seen in the F-22)

The issue with the PAK FA as it has been described to date is that it doesn’t not appear to be subject to the same tradeoffs that other aircraft are.

It is claimed to have the same or greater fuel capacity as the Su-35, and despite the addition of internal bays, additional avionics, and a larger wing it is claimed to be lighter. (indeed one person on this thread went so far as to say he didn’t think the PAK FA needed any additional internal volume to match the Su-35’s fuel capacity :stupid:)

The PAK FA is supposed to have greater supercruise capabilities than the Su-35, but match or exceed its range and endurance. How? It is all well and good for fanboys to wave their hands and say “improved aerodynamics” but that doesn’t come close to explaining how that could come about. Adding thrust in supercruise conditions, while improving fuel economy at regular cruise conditions, how?

The list goes on. One ultimately has to accept the various claims uncritically (wishfully concluding that Russia has unlocked secrets of aerodynamics, structural design, and propulsion unmatched anywhere in the world) or conclude that the claims are inflated substantially.

I can see which way most on this thread are going to go.