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Ultimately we can dance around this topic just short of calling each other stupid all we want, but the fact is, militaries are beginning to consider alternatives to the beleaguered JSF program, and some have already made purchases.

If I've made you feel that's what I wanted to say, then I have spoken badly and I am sorry. I respect you and I agree with a lot of what you have said. I have deep concerns about the compromises that have both apparently and presumably been made in the F-35 in order to support a configuration (STOVL) that only something like 15% of the planned production will use.

I appreciate the info you've provided. I don't put so much faith in Boeing marketing materials, and I believe that there are varying levels of stealth technology that may be exported depending on who the ally in question is, but you answered most of my questions.

Like Vifam, I'm curious to see if the future has a place for both the F-35 and developments of the F-15 and F-18 serving in similar roles. I feel that the F-35 has greater growth potential, but I don't doubt that its teething period will be painful.

Edited by Nekko Basara
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Likewise, I don't think you're dumb at all- the statement was just to point out the fact that this argument could turn into a name-calling squabble at any time, and that'd be counterproductive.

I try not to trust marketing people, but then there aren't any numbers the public is privy to, just claims from manufacturers.

Ultimately, the F-35 has to grow and succeed. It's cost too much to just drop it. We're stuck with it now, whether we like it or not.

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But it states that it gives "real-time imagery" (not just data) via infrared cameras.

https://www.f35.com/about/capabilities/missionsystems

Unless I'm reading wrong, it does suggest that the pilot can literally "see through the floor".

Found this:

http://www.rockwellcollins.com/sitecore/content/Data/News/2014_Cal_Year/GS/FY14GSNR44-F35.aspx

ITs not just through the floor, its basically a 360 degree spherical view around the aircraft utilizing an electro-optical system. The biggest value is the sensor fusion, so basically it will take information from other sensors, both onboard and off board and present that information to the pilot through the helmet system. That's unprecedented.

With all that being said, is there any reason any of that would be inherently unique to the F-35 anyway? It's not something radical to the airframe- you could put that in any plane. And you'd probably actually reach production in another aircraft.

It is for a number of reasons. First you need to basically run sensors all around the aircraft, power them, and then build an avionics and helmet system that takes all that data. That isn't really unfeasible, but its actually very costly and difficult to do. Its not being retrofitted into any other aircraft.

The real challenge is to integrate that data into the overall sensor picture. Most aircraft do not possess computing power/architecture to integrate such a system. The F-22 and F-35 are the only aircraft with a IEEE 1394 firewire data bus that can handle the sort of data that is required to make such a system a reality. it might be possible to run a separate system outside of the core legacy avionics system, but it wouldn't have any fusion with other sensor systems, which is the real benefit of the DAS system. Some test F/A-18F attempted this, where they basically ran a firewire line from optical systems to back seat laptops... but that is limited in its capability and really only represents a narrow capability, nothing like a secondary DAS-like architecture without sensor fusion.

So its really not possible.

The F-35 is in production in the same way that the highways around D/FW are under construction. Technically, yes, but we still don't really have anything to show for it.

There have 120+ training aircraft, which are starting to produce new pilots and crews for the aircraft. Moreover by July or August of next year the first operational squadrons will start to come online in Yuma.

By the same token, a lot of the foreign powers who pledged to buy it are having second thoughts.

Some, but this is balanced by new countries coming online and purchasing in larger than expected volumes.

With the F-16 and F/A-18 still in production and receiving updates, is a 5th-gen fighter strictly necessary? Especially considering who the actual intended buyers are. We keep talking about an "aging fleet" but really, what does it matter?

Oh it really matters. Basically aircraft are time limited by their airframe, which can only take a certain amount of flight time and Gs before they cannot be used anymore. The RCAF's CF-18s are basically representative of that, Early on they were flown extremely hard by pilots: they would regularly pull 9Gs and undertake multiple touch and go hard landings. It was quickly discovered that the aircraft were rapidly eating up their usable flight life and whole new flight restrictions were put into place.

Now we basically fly them like classic cars: they rarely see more than 4Gs, they are equipped with very specific loadouts and landings are conducted with a gentle flare touchdown. They are literally at the end of their lives and we need to soldier on. The USAF does not have the same regimented regulatory system on their F-16 fleets, but many aircraft are being retired at 5,000~6,000 hours, instead of the 8,000 expected lifespan.

Sad but true--what I call the "Ace Combat effect" is proving true. That is---the aircraft itself matters little, it's all about the sensors/weapons it uses.

Most current modern European F-16A's, are the F-16A MLU now. They are much better planes than an initial F-16C.

The F/A-18A+ is better than all but the very latest F/A-18C's.

None of these are airframe differences really, purely avionics and weapons upgrade.

So why are you paying a zillion dollars for an ASRAAM-carrying F-35 w/AESA radar, when you can pay a whole lot less for a Super Hornet that does the same, and is faster and more agile? That's what the RAAF did.

The Super Hornet is not faster, more agile or "as capable." If the Shornet is clean, its likely faster, but not more agile and certainly not as capable (especially in range or with weapons). Basically if you hang anything on the Rhino, its performance drops dramatically. With tanks, it could not get to M1.6... at least not without a dive. It doesn't have anything approaching sensor capability or comms that the F-35 has. And in reality the cost is likely on 20% less than the F-35.. maybe. Weigh that with better capability and higher sortie rates, and its really not a bargain at all. Much of those claims are basically Boeing business development talking points, which basically use a clean F/A-18E (without pods of external fuel tanks), using 2000 base year costs and comparing them to the F-35's 2012 base year costs.

The RAAF only purchased the Shornet because of the early withdrawal of the F-111: basically it was a gap filler. Its force structure in 2022 will be 24 F/A-18F (12 or 24 being EA-18G configuration) and 72 F-35. So its really not what the Aussies did.

Edited by Noyhauser
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All of that post completely ignoring the fact that Boeing is still building F/A-18s, and that the Block III shares very little in fact with the Block II architecture, which is practically a different plane in vaguely the same shape as the F-18.

But really, you're saying the reason the F-35's avionics upgrades can't be applied to any other plane is because they don't have super-USB?

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I'll be very interested to see the actual RAAF F-35 delivery numbers in the 2020's.

Prime Minister Abbott announced that 72 will be purchased. Since the deliveries will start in 2018, and so the RAAF has already started major planning for acquiring the fleet. Its basically a year or so away for them to start training their initial cadre of pilots. I'd say that 72 is likely what you will see in 2022, especially considering that the RAAF F/A-18A fleet will need to be replaced by 2022... as Australia does not have a centre barrel regeneration facility like the RCAF does in Mirabel Quebec. So those aircraft are life limited to that time.

For medium sized air forces like Canada and Australia, decisions like this are not taken likely. You have an established force structure that isn't easily tinkered with: airframe life, aircraft capability, availability and personnel arrangements, just to name a few. That means an announcement like this is very likely to be followed through... especially given the broad political agreement over the procurement.

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If I can go back to Mr. Sprey's critique of the F-35, something else had been bothering me. He places a lot of emphasis on its (supposed) lack of maneuverability, and ties this directly to its small wings and high wing loading.

Now, I realize that this is a gross oversimplification of the aerodynamics that contribute to maneuverability (if that can even be generalized as a single attribute), but it's not completely invalid. There is a problem even with this argument, however: the F-35C. Because the naval version of the F-35 has considerably greater wing area as well as larger control surfaces, can we safely assume that it had a lower wing loading and correspondingly better performance in attributes like turn radius? And, if this were a true detriment to the "base" F-35 airframe, why wouldn't the Air Force version, the F-35A, use the larger wings?

Going further, what is behind the small wings, anyhow? Mr. Sprey indicates these are a concession to the VTOL design, and looking at the few existing VTOLs I'm inclined to believe that, but why? Surely speed in vertical flight is so low that the drag of larger wings in this direction can't be significant (plus they can serve to trap some air when the craft is low enough for ground effect). Is it mainly about weight?

The best I can figure is that the downsides of the large wings for ANY version of the F-35 would be drag in forward flight/reduced speed, increased weight, more low-level, high-speed turbulence, and (to a minor degree) cost. The benefits would be superior maneuverability (particularly low-speed handling and reduced stall/landing speed), greater range from both higher lift and increased fuel space, and maybe a slightly higher ceiling.

Does that sound right? And, if so, does it make sense that the F-35A is sharing the wing of the F-35B instead of the F-35C? I'd love to hear your thoughts.

Edited by Nekko Basara
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(...) Does that sound right? And, if so, does it make sense that the F-35A is sharing the wing of the F-35B instead of the F-35C? I'd love to hear your thoughts.

What comes to mind in reading your post about the shared wings:

- reduced cost for the B model from shared parts with the A model

- the A model is oriented for flight at higher speeds and altitudes over land, where larger wings (+ fuel reserves) and lower speed performance aren't as important for day to day operations (mainly carrier landings).

Your thoughts on it sound right, but I'm afraid I can't provide any insight into why small wings other than the guidance from the oft quoted "you can make a brick fly if you put enough thrust onto it".

EDIT: just realizing that I may be inadvertently suggesting that the F-35 is a brick. Which is not my intent. It's that due to the high thrust, the wings are less of a factor, thus they don't need to be big to keep it in the air or something like that.

Edited by sketchley
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If I can go back to Mr. Sprey's critique of the F-35, something else had been bothering me. He places a lot of emphasis on its (supposed) lack of maneuverability, and ties this directly to its small wings and high wing loading.

Now, I realize that this is a gross oversimplification of the aerodynamics that contribute to maneuverability (if that can even be generalized as a single attribute), but it's not completely invalid. There is a problem even with this argument, however: the F-35C. Because the naval version of the F-35 has considerably greater wing area as well as larger control surfaces, can we safely assume that it had a lower wing loading and correspondingly better performance in attributes like turn radius? And, if this were a true detriment to the "base" F-35 airframe, why wouldn't the Air Force version, the F-35A, use the larger wings?

Going further, what is behind the small wings, anyhow? Mr. Sprey indicates these are a concession to the VTOL design, and looking at the few existing VTOLs I'm inclined to believe that, but why? Surely speed in vertical flight is so low that the drag of larger wings in this direction can't be significant (plus they can serve to trap some air when the craft is low enough for ground effect). Is it mainly about weight?

The best I can figure is that the downsides of the large wings for ANY version of the F-35 would be drag in forward flight/reduced speed, increased weight, more low-level, high-speed turbulence, and (to a minor degree) cost. The benefits would be superior maneuverability (particularly low-speed handling and reduced stall/landing speed), greater range from both higher lift and increased fuel space, and maybe a slightly higher ceiling.

Does that sound right? And, if so, does it make sense that the F-35A is sharing the wing of the F-35B instead of the F-35C? I'd love to hear your thoughts.

Not sure if the F-35A actually shares that same wings as the F-35B.

I would also guess that the F-35C weighs more than the F-35A due to extra strengthening needed for carrier use - thus requiring more lift from the larger wings.

Edited by Vifam7
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I found this fairly recent article which details the commonality in the F-35 family:

http://www.defenseindustrydaily.com/lightning-rod-f-35-fighter-family-capabilities-and-controversies-021922/

In particular, there is an excellent graphic about halfway down that shows the "unique," "cousin," and "common" assemblies. It appears that the wing skinning on each version is unique, but the internal structures are "cousins" between the A and B. The article also mentions that the A has the highest G rating, suggesting it might actually be the most maneuverable variant.

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The smaller wings are a concession for the stealth attributes the USAF is super hard-on for. Bigger wings present a higher stealth profile, and there isn't much you can do with design to cut it, leaving only expensive stealthy materials to absorb radar, and even those will only do so much. The Navy is less concerned with high passive stealth and more concerned with a usable aircraft, so the 35C has big wings. The Air Force doesn't absolutely need the big wings, so they opted for the higher-stealth tiny-wing variant.

The B variant shares similar wings because cost cutting. This isn't an F-22 where we can make it out of unicorns and gold-plated turboencabulators, it does have to meet cost requirements. (Which it's still having a hard time with)

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Guess we're getting back to that pre-Vietnam no a/c mounted guns mentality.

and we already went over how the "that's what they said before vietnam" argument was irrelevant and stupid because radar and missile tech doesn't suck anymore. The only need for guns on a plane like the F-35B/C is CAS and for that they have an optional external pod.

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The smaller wings are a concession for the stealth attributes the USAF is super hard-on for. Bigger wings present a higher stealth profile, and there isn't much you can do with design to cut it, leaving only expensive stealthy materials to absorb radar, and even those will only do so much. The Navy is less concerned with high passive stealth and more concerned with a usable aircraft, so the 35C has big wings. The Air Force doesn't absolutely need the big wings, so they opted for the higher-stealth tiny-wing variant.

Hmm, I thought that with proper stealth shaping, the physical size of the object was not very important, because you had minimized its reflection in a given aspect (or aspects). It's like looking at a piece of paper - if it's exactly edged-on, you can barely see it, and it doesn't matter much if it's the size of a business card or a poster board (assuming hypothetical paper of the same thickness that doesn't warp). A stealth aircraft is shaped to be as close as possible to the reflective equivalent of that piece of paper in the "eyes" of a radar at the most likely angles of interception, and likewise to confine any necessarily reflective aspects to a few discrete angles. So, the size of the wings shouldn't matter very much to its stealth, unless we're talking specifically about those least-optimal scenarios.

Or... maybe I don't get this at all. Stealth is some pretty hazy stuff.

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All of that post completely ignoring the fact that Boeing is still building F/A-18s, and that the Block III shares very little in fact with the Block II architecture, which is practically a different plane in vaguely the same shape as the F-18.

In reality AMC III on Block III is not really close to the capability as the 3i avionics package that will be installed on F-35 after 2017. Its data will still be presented in a semi-federated state to the pilot (not fused in the way that the F-35's will be), and it too uses the MILSTD 1335 Databus which limits the amount of data that can be transferred. The biggest enabled capability is a digital touch screen and cockpit displays, and some processing capabilities, but it still is limited in a whole bunch of key areas.

Moreover the F/A-18E won't be produced for much longer. The Navy wanted 22 additional EA-18Gs (not F/A-18Es) in its unfunded priorities list this year, and it got 5. In reality the US Navy hasn't made a large purchase of F/A-18E/Fs in several years and the EA-18Gs will primarily be tasked to jam for the existing F/A-18Es . The five units staved off the line closure for an additional year, but its almost certain that the St. Louis plant will be closed down in 2017.

But really, you're saying the reason the F-35's avionics upgrades can't be applied to any other plane is because they don't have super-USB?

Its not a USB: the Databus is a critical component for bringing in data from federated sources: RWR, Radar, LANTIRN/LITENING pods, weapons, Comms, diagnostic sensors, among other things and sending processed information to flight displays, automated systems and communication. This is the Eurofighter's Avionics infrastructure diagram:

EurofighterAvionics_zpsb3c84c33.jpg

Those red and green boxes are the data buses; They are integral to the functioning of a fighter's avionics system. In the case of the F-22, they actually fused the radar with the core processor in order to improve the data transfer rates. So being dismissively flippant about the quality of data bus really illustrates your lack of understanding of this area.

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Dude, IEEE 1394 is basically just a standard for serial bus data transfer, with numerous similarities to USB. It's not even as complex or inelegant as CAN Bus in cars if it uses IEEE standards.

If that's the case, it's just a matter of replacing avionics gear with more modern equipment. As if that's never happened before.

I just don't see the big deal. It's not like it's some crazy stealth material, shape, or exotic control surface. It's not something that is part of the airframe, it's just computers.

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Holy crap! I've read about the Israeli F-15 that landed missing a wing, but I never saw a Tomcat flying with that kind of damage!

post-265-0-38857900-1414170571_thumb.jpg

Chris

Edit: apparently it too landed safely!

The first photo depicts the F-14A BuNo 159832 side number 205 which on Jun. 29, 1991 experienced a mid-air collision over South Chinese Sea with another Tomcat, the BuNo 161597 side number 201. Both aircraft were from Black Lions of the VF-213, at the time embarked on the USS Abraham Lincoln (CVN-72) and while the 201 crashed into the sea where the crew was rescued, the 205 was able to land to Singapore after loosing part of its right wing.

Edited by Dobber
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I can see that. Other than the cockpit and engines the space between the engines is flat

If you slice an F-14 right down the middle, nose to tail----you'll get almost a perfect classic airfoil shape. The "trailing edge" is achieved by having the beaver-tail so thin that there is almost no structure, purely the external skin itself----you can see right through that area when the airbrakes open.

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The smaller wings are a concession for the stealth attributes the USAF is super hard-on for. Bigger wings present a higher stealth profile, and there isn't much you can do with design to cut it, leaving only expensive stealthy materials to absorb radar, and even those will only do so much. The Navy is less concerned with high passive stealth and more concerned with a usable aircraft, so the 35C has big wings. The Air Force doesn't absolutely need the big wings, so they opted for the higher-stealth tiny-wing variant.

The B variant shares similar wings because cost cutting. This isn't an F-22 where we can make it out of unicorns and gold-plated turboencabulators, it does have to meet cost requirements. (Which it's still having a hard time with)

No, that's entirely incorrect.

Size has an near infinitesimal effect on observability. you can have an infinitely long wing and angled correctly it won't matter. Conversely, an incorrectly positioned panel a few centermeters across will be detected by most modern fighter radars.

Wing size is completely dependent on the navy's need for low speed handling, versus the general balance of flight characteristics that the AF wants for its version.

If I can go back to Mr. Sprey's critique of the F-35, something else had been bothering me. He places a lot of emphasis on its (supposed) lack of maneuverability, and ties this directly to its small wings and high wing loading.

Now, I realize that this is a gross oversimplification of the aerodynamics that contribute to maneuverability (if that can even be generalized as a single attribute), but it's not completely invalid. There is a problem even with this argument, however: the F-35C. Because the naval version of the F-35 has considerably greater wing area as well as larger control surfaces, can we safely assume that it had a lower wing loading and correspondingly better performance in attributes like turn radius? And, if this were a true detriment to the "base" F-35 airframe, why wouldn't the Air Force version, the F-35A, use the larger wings?

Going further, what is behind the small wings, anyhow? Mr. Sprey indicates these are a concession to the VTOL design, and looking at the few existing VTOLs I'm inclined to believe that, but why? Surely speed in vertical flight is so low that the drag of larger wings in this direction can't be significant (plus they can serve to trap some air when the craft is low enough for ground effect). Is it mainly about weight?

The best I can figure is that the downsides of the large wings for ANY version of the F-35 would be drag in forward flight/reduced speed, increased weight, more low-level, high-speed turbulence, and (to a minor degree) cost. The benefits would be superior maneuverability (particularly low-speed handling and reduced stall/landing speed), greater range from both higher lift and increased fuel space, and maybe a slightly higher ceiling.

Does that sound right? And, if so, does it make sense that the F-35A is sharing the wing of the F-35B instead of the F-35C? I'd love to hear your thoughts.

The reality is that Sprey is wrong and an exceptionally biased information source. Even in the 1970s he was discredited as an analyst. He was dead set against the F-15 and F-14, as being too complex... even the F-16 was seen as being excessively weighted down. Today he claims that he was "designer" or key influencer of it and the A-10, which is just not true. But lets get onto the thrust of his arguments.

First his calculations on wing loading did not include the F-35' fuselage, which is a lifting body, as you noted in the F-14 case. That changes quite a bit. Second, there is so much more to air combat to wing loading. In reality sustained turn is not the most sought after performance metric. The advent of all aspect, high off boresight missiles, basically has switched what performance variables matter relative to others. Rather than Acceleration and sustained turn being prized, Acceleration and instantaneous turn have become more important as these allow for sudden movements that can help an aircraft point its nose towards an adversary faster, or to quickly reposition itself on the defensive. Others that have increased in importance are High G Roll rate, low speed nose authority (post stall/high AoA conditions), time to corner speed.

So, back to your question, the current wing design basically is a trade off that enables the aircraft to have the performance in those other realms. Smaller wings basically aid in acceleration, instantaneous Turn, high G, ect... all the stuff that have become more important for current air combat.You won't see great swirling dogfights of the old. Rather it will be a few violent turns within close quarters with one or both aircraft going down. That's not to say that the F-35 doesn't have a good sustained turn rate.. most of the comparisons are made with the early F-16 blocks, which were extremely maneuverable. Its just not as valuable as it was before.

As a final point, The JSF's real concession wasn't the B version, that's a fallacy. In reality the biggest concession came from the C version, because of the extra reliability requirements the navy imposed on the aircraft. ITs heavier today because the Navy wanted an excessive amount of redundancy built in for carrier operations, including reinforced structures throughout the airframe.

Hmm, I thought that with proper stealth shaping, the physical size of the object was not very important, because you had minimized its reflection in a given aspect (or aspects). It's like looking at a piece of paper - if it's exactly edged-on, you can barely see it, and it doesn't matter much if it's the size of a business card or a poster board (assuming hypothetical paper of the same thickness that doesn't warp). A stealth aircraft is shaped to be as close as possible to the reflective equivalent of that piece of paper in the "eyes" of a radar at the most likely angles of interception, and likewise to confine any necessarily reflective aspects to a few discrete angles. So, the size of the wings shouldn't matter very much to its stealth, unless we're talking specifically about those least-optimal scenarios.

Or... maybe I don't get this at all. Stealth is some pretty hazy stuff.

A good primer is Rebecca Grant's the Radar Game, which she updated in 2010.

https://secure.afa.org/Mitchell/reports/MS_RadarGame_0910.pdf

Edited by Noyhauser
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