Why does these two aircrafts use different nozzles anons?
F-35 is an aircraft that is around one and a half decade younger than Raptor but it still uses conventional nozzles. So my question is, why?
1- Did they realize that trust lost with RCS reducing design was not worth the reduction if there was any trust lost
2- Did it cost too much for a ''light weight multirole aircraft''
3- Was stability an issue with that design in one engine configuration
4- Or did they had to design a new nozzle because F-22 had trust vectoring and trust vectoring nozzle effected radar cross section of the aircraft too much to not to add it?
t. Curious Military Acedemy student from Turkey.
It was a design tradeoff to reduce cost. The F-35 isn't designed to be a Mach 2.0+ fighter like the Raptor so it only has one engine with no thrust vectoring. The idea is that the F-35 is mechanically simpler and thus cheaper to maintain than the Raptor.
>F-35 is an aircraft that is around one and a half decade younger than Raptor but it still uses conventional nozzles. So my question is, why?
The F-35 nozzle is actually the better of the two, it doesn't have the trade-offs of the Raptors nozzle (turbulent flow etc.) but is still stealthy
If you take a closer look at the F-35 nozzle, you'll see that the single elements are arranged in an x-like faction to each other and aren't simply round, just take a look at the su-27 nozzle posted by >>28519871
F-22 nozzles appear to be more expensive and complicated due to the materials used. Since the F-35 didn't have a thrust vector requirement I assume they went with the cheaper alternative. Also the F-35 has one fuckhuge engine so I imagine the designers went with whatever was most effecient.
Basically the retangular nozzle on the YF-23 (because on the left isn't an F-22 but a YF-23, which didn't use thrust vectoring) is a way to reduce the IR signature of the engines, as Heat Seaking sensors are fairly limited in their range by atmospheric density and dissipation, so to lock onto a distant heat source you've generally needed to cool down the heat sensors more, which hits diminishing returns and makes them fuckers to use and maintain fairly quickly due to thermodynamics, so even a mild reduction in IR signature (like how the A-10 have its jet wash go over the top of its tail) massively reduces the range at which traditional heat seeker missiles can actually lock on to a plane.
(at least until metamaterial based heatsensors start hitting the arms market).
The Downside to retangular nozzle based IR stealth like that is that you need fancy and expensive materials, and you need to do special maintenance routines for them and do special pre-flight checks to make sure there's not say a crack in them that undermines the stealthiness.
So for the F-35 which didn't really bother that much with all aspect stealth in favor of focusing on front aspect stealth for the purpose of its primary role as an interdictor and 5th gen wild weasel platform.
Specifically why the F-35 doesn't do 3d thrust vectoring is an even easier answer too: it doesn't need it.
It's already fairly super-maneuverable (as the YF-23 was) without thrust vectoring or canards, it has off-bore-sight aiming capabilities (which have been found in wargames to give non-supermaneuverable planes the ability to dogfight on par with super-maneuverable ones, to the point where a few F/A-18s have F-22 silhouettes from simulated kills in war games painted on them) and so the increased complexity and maintenance costs of thrust vectoring would be completely wasted.
Dammit, could have sworn that hump on the left plane on OP's pic was characteristic of the YF-23, but yeah, it is an F-22 due to the lack of a "thigh gap" between the engines.
- commonality with the B version was required. B needs round nozzle for vertical landings.
- the plane is already underpowered it would be worse with a square nozzle
- trust vectoring would add weight, see above
RCS on the round nozzle is much larger. It's only somewhat stealthy in x-band
you cannot hide two 80MW heat sources.
lockheed loves to get paid for shit that doesn't do anything.
see also: stealth features on sr-72
You can't make it invisible in absolute terms, no, but you can't make an aircraft radar invisible either.
But in both cases, you can significantly reduce the detection range, terminal guidance aquisition range, and the reliability of seeker heads under defensive manuvers. Which is the entire point.
1900 km is closer to Mach 1.8, actually. The top speed only goes down to Mach 1.6 when carrying a full internal load. An F-16 carrying the same amount of load would be even slower.
Why all the lockheed hate on /k/? Seriously, I never understood it. They've produced some of the highly iconic and "cool" airframes of the past 80 years. Pic related is my face.
I'm not a LM fan; not really a fan of any one specific manufacturer. But it always blows me away how little /k/ seems to know about how bleeding edge aircraft are developed and procured contrasted against how incessantly loud they are about it.
Fuck it. This is now a LM aircraft thread and companies which were bought by/part of LM now (like General Dynamics)
*F-4 and F-14 sold separately
Yes, I know the F-4 is MD and the F-14 is Grumman. Just thought it was a cool formation.
Don't often see these two ladies together, living at opposite ends of the speed bell curve for recon aircraft as they do.
Much maligned as a multi-role but perfectly decent as an interceptor. Somehow feels right not only to give it Ferrari colors for speed but also that it be Italian for faintly implied incompetence.
Reminder that GD is now parted out and part of LM, so that F-16XL falls under the LM umbrella now.
Because a significant portion of the /k/ userbase is lay yahoos reading articles written by other lay yahoos like Gary "War Nerd" Brecher(sp?) or David Axe.
To the extent that anyone here actually knows anything from actual experience, they only know whatever tiny little bit they are involved in.
kek does that make the F-16 shit show when it entered service LM's fault too?
I'm old enough (just barely) to remember all the media feeding frenzy over the F-16 "lawn dart" to be finally dying down in the early 80's. This shit over the F-35 or even F-22 is nothing new, and edgemaster ignorants who think themselves out on the edge for shitposting about new airframes are facepalmingly ignorant of history.
See: F-106, F-4, F-8, F-14, F-16 just off the top of my head for programs with significant issues and massive media flack.
Running out of constantly reposted pics, folks. Help a niqqua out.
Though this one incident is almost enough to justify the LM hate... That poor Valk
That's all I got.
We now return you to our regularly scheduled shitposting.
>ITS A MEME YOU DIP
It used to be a meme. Now it's the unholy abortion of Poe's Law, like so much else on /k/. The meme is only funny if at least a quarter of the people spouting it actually get it (it's too much to ask that half of em don't believe it).
Don't forget the Abrams and M16 getting bashed.
Pretty much every piece of new US equipment is always made out to be the absolute worst thing ever at first.
That is until it slaps the shit out of everything thrown at it.
It is a combination of things.
1)Projects are made public in testing phase, when the projects are bound to have myriad of problems.
2) Public media that likes "government boondogle" stories.
3) A public culture that likes to consume "government boondogle" stories.
4) Government factions that perpetuate the sentiment, like GAO, whose job it is to literally find and make public every flaw that they can find.
5) Foreigners that see the US as this entity that is either evil or delusional and full of itself. Where criticizing US projects is a matter of national pride.
This is not some meme. Two or three years ago the general sentiment in /k/ about the F35 was that it was dog shit.
But the DOD has learned, hence why we know little about the LRSB, despite it being scheduled to enter service in 2020.
Busting Myths video guy here:
Main issue would be weight; thrust vectoring mechanisms can add another thousand pounds or so of mass onto the rear of the jet, and the F-35 is already statically unstable in pitch.
Cost would obviously also play into the design, as the jet is meant to be relatively easy to maintain.
As for RCS, the LOAN (Low Observable Asymmetric Nozzle) is fine - the only places it creates vulnerabilities is if enemies are above / below you and slightly behind you, with mechanically gimballed AESAs / PESAs manually pointed downward. Even then the shaping would disrupt their returns as they moved around. More importantly though, the F-35 pilot should have already detected their IR signature via DAS or been alerted to their radar emissions via ESM.
Ground radars would only get a passing glimpse, which isn't useful for getting a targeting solution.
Both engines do also have internal RCS reduction measures in their reheat and turbine sections.
Lastly, by not being actuated in just 2 dimensions, a circular nozzle has the advantage when it comes to efficiency as it can produce a better convergent-divergent nozzle.
I'll don't understand why the US government was so protective of the F-22, but they're so open with the F-35. I mean, the F-35 is more advanced in every way except kinematic performance right? They completely blocked any hope of exporting the F-22 to other nations.
There's 2 main reasons:
1. When Congress blocked export of the F-22, there was no PAK-FA, there was no J-20, there was no J-31. They thought that the F-22 was 20-30 years ahead of the pack, so they wanted that to keep that only to the US (giving it to others might lead to espionage, etc - ignoring espionage in the US).
2. The F-22's software isn't protected on the actual aircraft, not not very well, meaning that if a spy got into a maintenance hangar with an F-22 and hooked up a proper laptop to it, they could essentially copy-paste the source code onto USB. When a bunch of F-22s had their computers crash from crossing the international date line, they were able to land the jets in Hawaii and fix the software in about a day because of this.
On the F-35, that software is under lock and key; you'd need to hack into the central code repositories to get the source code, or spend a millennia using super computers to decrypt the software. Adding the same security measures to the F-22 wouldn't be that hard, but it'd still cost millions of dollars and the F-22 is already starving for $$$ when it comes to vital upgrades (even F-16s have JHMCS while the F-22 has no helmet mounted cueing).
>Implying detection (thermal or otherwise) is a constant, binary thing, and not highly variable and dependent on numerous factors
>Implying reduction in thermal signature doesn't demonstrably reduce the range and effectiveness of IR-based threats
>Implying reducing the depth of the exhaust plume doesn't reduce thermal signature
>Implying promoting the mixture of the exhaust plume with the cool surrounding air doesn't reduce thermal signature
>Implying countermeasures don't exist
>Implying jets run full-afterburner all the time
>Implying a pilot can't reduce throttle on his two "80MW heat sources"
I think what he was arguing is, that you cannot reduce the infrared radiation of the engine itself - you can cool the exhaust gases but not the component, not effectively at least - same as the surface of the aircraft.
>What people seem to forget is that the technically superior Hurricane didn't win the battle of britain -- the cheap spammable spitfire did.
The Hurricane was a great fighter but was in no way superior to the spitfire. I'm almost certain the Hurricane was the cheaper of the two also.