FBWSo the F-35 has max survivability in DCA.
It is as good or better than the F-22.
Who believes that?
Kindly point me to where the F-22 was evaluated in the Danish competition. It is not rocket science, each category had a set of criteria. Meeting them all would be commensurate with a rating of 5 based on Danish requirements. Any school teacher could tell that more than one student can score a 100% on one test, yet get very different grades in another subject.
In what way it can have max survivability in CAS?
By staying at 5,000 meters altitude?
Looks like BS data to confirm a decision made for political reasons.
Why do you relate close air support with flying a low altitude? Should the B-1 that flew a large proportion of CAS missions in Afghanistan fly at treetop height to fit your definition of CAS? Seems to me you need to update your thinking before claiming B.S. on the report
For the record, I’m not sure what I make of the report. The methodology on the cost analysis is explained somewhat to my satisfaction, though even the most ardent supporter would acknowledge that the Danish used the best case scenario for F-35 considering the variance in the cost projections. As for the scaled mission effectiveness, ect, the methodology is not as well explained, other than stating that some evaluation was based on simulators, ect. (it is possible that how they evaluated effectiveness on criteria that has been omitted from the publically available report)
FBWAmazing how can someone give the F-35 5.0 survivalability marks without even raising eyebrow.. Traditionally primitive reasoning in style “oh, they write it’s stealth that means it can’t be shot down”..
No, I believe that is you projected your narrow view that survivability means “stealth” to the evaluators. I’m sure they took into account how the AN/ASQ-239 and AN/AAQ-37 coupled with the signal and image processing algorithms, not to mention limited aspects of cognitive EW algorithms included now and to be expanded in the future. Add to that ALE-70 countermeasures and the developing EW abilities of the APG-81, and the score (as compared to the competitors) is no surprise.
As a comparison, the Typhoon DASS system has been found wanting, PE2 upgrades have been slow , and currently critical upgrades to Praetorian DASS are not planned again until P4E. The SHornet’s AN/ALQ-214 part of the IDECM is a relatively new system that has already been upgraded three times.
FBWHave you? Western Ukraine that was welcoming Hitler was part of Poland when famines in USSR took place in 1932-33. Western Ukraine ideologically, culturally and even ethnically is fairly different from the rest of Ukraine. There is a reason why Ukrainian government is scared of federalization (if it is good enough for US, UK, Germany, Russia then it should be good enough for Ukraine), they know if at some point referendums take place people will show middle finger to Ukraine. But no, they artificially try to hold people in this Ukrainian cage through unitary state, gathered by communists from parts of various countries (too greedy I guess, got their own independence but cannot grant independence to others), but they can’t hold them there forever with such terrible economical and political state of affairs. If USSR (and many other countries) could dissolve then Ukraine can too, they don’t and shouldn’t have privilege here.
I hesitate to answer you as I’m not going to get drawn into a discussion over the current contested regions. I will just say that your characterization that only the areas around Rovno or Ternopil that welcomed the invasion is not accurate (though there is considerable revisionist history attempting to show this was the case). Areas around Kiev and Zythomyr, that were in the heart of the Holodomor saw the invaders as liberators, at first.
As you probably know what areas in Eastern Ukraine were not affected severely by the Holodomor and why, I’m sure you know why they were not as welcoming. But none of this is related to the aviation topic at hand and discussion of this will obviously lead to politicization of past history due to present events.
FBWGood Lord well speak for yourself. Western democracy is a total sham. Example, Finnish government one year after elections is conducting an aggressive thatcherite campaign of privatization but before the elections none of the coalition parties had announced that privatization would be there intention. They also want to find reason to subjugate Finland to NATO although most of the governing coalition had rejected that in their election platforms. :rolleyes:
Don’t worry by 2025 nato too will get many surprises. :applause:
good lord, this guy is like an angry JSR without the economic babble. Another brylient mynd destroyed by Sputnik news.
FBWCost reduction for F-35 lots seem to start to plateau: given that current ‘low’ rate production is already as high as full rate production of Super Hornet, I believe that they have made most of the available cost savings already.
Of course at present, there is not enough Super Hornet orders to keep the line open, much less cost-effective, for 2020’s. They need to score export orders quick and that doesn’t seem to be happening (or convince USMC to buy it – but that ain’t happening either). Strangely, SHornet seems to compete poorly against European fighters even though it should be cheaper than them. Well, of course political scandal destroyed Brazilian bid, but they didn’t even participate to Swiss fighter contest.
No, the cost curve should continue to trend downward. The difference between lots 7 & 8 was 4 million per aircraft (for the A model) and lot 9 should be over 1 million less than lot 8. Once full rate production starts, the unit costs will drop further. The real issue is whether P&W will get a handle on the production costs for the F135 (still way high), the F-35 will be under $ 100 million before full rate production.
FBWPost from Marcellogo:Original mission for F-22 was to be an Air Dominance Fighter: the idea was that the stealth would allowed to extend Air Superiority /Supremacy well inside a major enemy controlled territory instead that just over the battle lines.
It have to be noted that it was envisaged that F-22 wouldn’t have needed to operate in counter aviation missions i.e. directly attacking enemy air bases to achieve that, just loitering aroung and engaging fighter planes that would eventually dare to take off.
Many of the more costly and troublesome features of F-22 came out from such an initial, let’s just say just excessively ambitious requirement.
This was not the mission of the ATF as envisioned, nor the F-22 as developed. There was no loiter whatsoever as a requirement. The ATF was envisioned as an air superiority fighter with short field capability (thrust reversers), superior agility (in the newer metrics), low observables (written in after the initial RFI), the ability to fly the majority of combat time over enemy territory in super cruise. Possibly more I am forgetting off the top of my head. The ATF project evolved around the idea that airfields would be under attack in a NATO-Warsaw Pact conflict. The ATF would be able to use airfield dispersion, high sortie rate (bit of a joke now), and would operate primarily in AFCENT theater where it would take off, accelerate to supersonic speeds as it crossed into enemy territory to engage and destroy enemy frontal aviation before they could support WARPAC thrusts.
, actually no other 5-gen fighter plane in development just sport things like flat noozles or try to achieve the same overall level of stealth reduction in all directionsjust because they would be used along very different, more conventional roles in which such features are not deemed necessary or better said not worth the extra cost and complexity they bring.
EDIT: I have added the part in Italic for clarity sake.
As I stated, the 2-d wedge nozzles were chosen for more than one reason: LO characteristics, lesser cooling requirements to meet IR signature, lower drag, excellent performance in dry thrust, ease of fitting thrust reversers (as was part of the original requirements).
Other “Fifth Gen” don’t use them because they have different design goals, in that the requirements are valued differently than in the F-22. The F-35’s LOAN nozzle meet the LO requirement, is less mechanically complex, and the advantages to be gained in vectoring thrust in pitch for a single engine aircraft are not worth it. Not to mention the need to swivel and spread out the heat footprint for the “B” model. The other two, J-20 and PAK-FA, most likely have different design objectives.
There is no best or worst nozzle in this case. The PAK-FA uses a 3-d thrust vectoring nozzle because the RuAF values super maneuverability at slow speeds most likely (that is not to say that the 2nd stage engine will repeat this, for all we know they’re in the process of trying out different nozzle configurations to meet the requirements). The US did not find value in 3-d thrust vectoring (found little yaw response and excessive leakage, but that could have been due to modeling with closely spaced engines or whatever), and they found it hard to meet the drag and signature goals. The J-20 is an odd fowl that seems to have design requirements unique to the Chinese, but it is important to note that the Chinese are still working out the engineering problems with turbofan design, so they might have taken a KISS approach.
FBWAll F-22 posts from the last two days from the PAK-FA thread I copied and pasted here with the OP listed at the top of each.
FBWPost originally from Marcellogo:
Quote Originally Posted by haavarla View Post
It may have been part of the Tactical game back in the 90’s(F-22 IOC in 2006 anyway, so moot point)
But today, the F-22 has no chance operating over enemy contested airspace. Certainly not in the way you refering to above. Not in Advance AoD airspace, China, russia etc
WE HAVE EXACTLY THE SAME OPINION THEN.
F-22 was designed around a well determined mission with absolutely no compromise in everything was deemed necessary in order to be able to perform.
However, also with such an effort, original mission turned out to be impossible against updated, stealth conscious, air defense systems and so F-22 production was interrupted prematurely at 185 and so F-15C Eagle will be retained in service until the 2030…
Scariest thing is that the idea of an air dominance fighter is still there also for the 6th gen one…
FBWPost originally from Eagle:
The F-15C A/G role in USAF service was dropped very quickly, and the F-22 was never intended as an F-15E replacement. Designating the Raptor F/A-22 came up much later after the design had been finished , in an attempt to sell it to politicians as multirole to get some more airframes. That didn’t work out so it was reverted to F-22 when it entered service.
I don’t know however if some sort of A/G capability was part of the initial requirements.
FBWPost originally from Haavarla:
Quote Originally Posted by Marcellogo View Post
Original mission for F-22 was to be an Air Dominance Fighter: the idea was that the stealth would allowed to extend Air Superiority /Supremacy well inside a major enemy controlled territory instead that just over the battle lines.
It have to be noted that it was envisaged that F-22 wouldn’t have needed to operate in counter aviation missions i.e. directly attacking enemy air bases to achieve that, just loitering aroung and engaging fighter planes that would eventually dare to take off.
Many of the more costly and troublesome features of F-22 came out from such an initial, let’s just say just excessively ambitious requirement.
So, actually no other 5-gen fighter plane in development just sport things like flat noozles or try to achieve the same overall level of stealth reduction in all directionsjust because they would be used along very different, more conventional roles in which such features are not deemed necessary or better said not worth the extra cost and complexity they bring.
EDIT: I have added the part in Italic for clarity sake.
It may have been part of the Tactical game back in the 90’s(F-22 IOC in 2006 anyway, so moot point)
But today, the F-22 has no chance operating over enemy contested airspace. Certainly not in the way you refering to above. Not in Advance AoD airspace, China, russia etc
FBWPost from Marcellogo:
Quote Originally Posted by RadDisconnect View Post
What kind of mission are we talking about here? Interception? Combat air patrol? OCA or DCA?What exactly was the original mission of the F-22? As far as I know it was made to be an air superiority fighter. I don’t know why you’re insisting that loitering over IADS was the design driver of the F-22 and its stealth features.
That being said, the T-50’s lower emphasis on all aspect stealth points do different mission requirements by the VVS, but the details of that are unknown.
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Do you have further readings about the matter? I’m curious.
Original mission for F-22 was to be an Air Dominance Fighter: the idea was that the stealth would allowed to extend Air Superiority /Supremacy well inside a major enemy controlled territory instead that just over the battle lines.
It have to be noted that it was envisaged that F-22 wouldn’t have needed to operate in counter aviation missions i.e. directly attacking enemy air bases to achieve that, just loitering aroung and engaging fighter planes that would eventually dare to take off.
Many of the more costly and troublesome features of F-22 came out from such an initial, let’s just say just excessively ambitious requirement.
So, actually no other 5-gen fighter plane in development just sport things like flat noozles or try to achieve the same overall level of stealth reduction in all directionsjust because they would be used along very different, more conventional roles in which such features are not deemed necessary or better said not worth the extra cost and complexity they bring.
EDIT: I have added the part in Italic for clarity sake.
FBWPAK-FA thread sorry about this aside commentary:
Rad- I don’t have many of the studies anymore but a quick google of “non axis symmetric 2-d nozzle” should yield some results. There is a particular one from NASA that researched the SERN nozzle and 2-d wedge nozzle (as well as others) that were studied prior to the ATF program. The F119 was eventually fitted with both in the YF-23 and YF-22 respectively. The F-111 rear fuselage and nozzles went through extensive iterations in testing. They never really solved the drag issue completely. An oft-repeated (not sure on the truth of it, not an aerospace engineer) was that removing the “tail feathers” from the F-15C resulted in a 3-5% increase in drag, just to give an idea of how critical nozzle shaping is.
As far as cooling, the research into active cooling of the LOAN nozzle is available, information on the F-22’s 2-d wedge nozzle’s cooling system is sparse (other than vague statements that the outer portions of the engine including the afterburner section and nozzle include active cooling measures to reduce IR signature).
FBWPost originally from Rad disconnect
Quote Originally Posted by Marcellogo View Post
The shoot, turn around and run was a standard tactic used by soviet interceptors and frontline fighters with their middle range missiles, always carried in pairs, one IR and the other Sarh, so i’m quite curious why you limit it only to Mig-31.
What kind of mission are we talking about here? Interception? Combat air patrol? OCA or DCA?
Quote Originally Posted by Marcellogo View Post
Suicide pattern is a way to describe how it would turn out to be trying to utilize the air dominance mission pattern originally intended for F-22 use i.e. sending a plane to loiter over enemy controlled territory against a modern air defence system, it doesn’t in any way imply that F-22 cannot turn out the great fighter it is when employed in another, more realistic way.
Just I doesn’t expect that any future 5gen fighter plane to be designed with the same all round RCS level reduction scheme as the relative advantages it bring are not in any way enought to justified the cost, both monetary than in terms of performances and reliability it would imply.
For the rest, same US MoD seems to have come to the same conclusion and have stopped its production in favor of F-35.
What exactly was the original mission of the F-22? As far as I know it was made to be an air superiority fighter. I don’t know why you’re insisting that loitering over IADS was the design driver of the F-22 and its stealth features.
That being said, the T-50’s lower emphasis on all aspect stealth points do different mission requirements by the VVS, but the details of that are unknown.
Quote Originally Posted by FBW View Post
The F119 has been fitted with SERN nozzle, two-dimensional non-axis symmetric con-di nozzle, and LOAN nozzle. The difference for the SERN nozzle (as would have been fitted to the F-23) was something like 1.5%. The actual thrust vectoring non-axis symmetric con-di nozzle has little impact on thrust, with the caveat that altering the pitch angles does reduce efficiency. Take a look at the SERN nozzle on the F119 fitted to the YF-23, truly bizarre. The SE611, and SE614 variants that powered the two JSF x-planes the asymmetric LOAN nozzle and do produce more thrust, but are different from the F119 in having an extra stage and larger fan.The studies indicated that the traditional con-di nozzle had a 10% advantage over non-axis symmetric con-di when considering nozzle weight. Then, when the optimal shape ( illustrated by the F119 engines) was compared with cooling requirements, the non-axis symmetric nozzle was within 1% of the standard con-di nozzle.
SERN nozzle? Also, I’m not aware of the F119 using active cooling for the nozzles.That’s the first time I’ve heard of that. Can you point me to a source? I’m rather curious
.
Quote Originally Posted by FBW View Post
The major advantage seldom mentioned is that the 2-d wedge nozzle offers a significant reduction in drag. The nozzle is a significant source of aerodynamic drag. The F-111 is a great example of this: the designers chose the nozzle that offered the highest thrust potential (uninstalled), unfortunately the nozzle had a significant performance penalty installed (one reason for the “turkey feathers” on the F100). The 2-d wedge con-di also offered advantages in dry thrust settings.
I haven’t heard about the nozzle thing. Based on johnwill who worked on the F-111, for the tail it turned out that a blunt end is somehow less draggy than a sharp end as was found in wind tunnel testing. Rather interesting phenomenon, and I’m not sure if it’s due to the nozzle or some other effect.
From johnwill himself:
Quote Originally Posted by johnwill
Don’t be so sure the sharp trailing edge will result in lower drag. As you say, there’s more to the story. Here are two photos from the early F-111 flight test program showing exactly the comparison under discussion, sharp edged and blunt.
The sharp edge was the original design, but wind tunnel and flight test showed the blunt edge resulted in a useful drag reduction. The pointy ended pods just inboard of the horizontal tails were also truncated for production airplanes.
Sharp eyed readers will notice those are Navy F-111Bs, but all production airplanes had the blunt design.
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Quote Originally Posted by FBW View Post
So, in no simple terms: While the symmetric con-di may be more efficient (ceteris paribus) on a test stand, it is not when installed, especially considering the original studies included a large (up to 600lb) penalty for the non axis symmetric nozzle.Back to the Pak-fa, why not flat nozzles? Perhaps because the designers wanted thrust vectoring on the pitch and yaw axis, or maybe because they did not want to basically redesign the entire afterburner assembly, jet pipe, for an interim engine.
Do you have further readings about the matter? I’m curious.
Quote Originally Posted by Mercurius View Post
The F119 engine weighs about 4,000 lb, so is in the same weight class as the F100 and F110.
According to the best data I have, the F-22 weighs 14.4 tonnes when empty, and can carry 8.2 tonnes of fuel internally.
Official data for the F-22 is that empty weight is 19,700 kg, so your figure may be weight without engine installed. The fuel load is 18,000 lb, so around 8.2 metric tons. There was a technical order floating a while back that suggested slightly higher fuel load, but every source that came after always pointed to 18,000 lb, so it may be an error in the order. The F-22 does have rather low fuel fraction, which is actually one of its greatest shortcomings: limited range, especially for the Pacific.
It seems like the PAK FA won’t have problems with range. I think all was stated was that the T-50 has more fuel than the Su-27 (20,700 lb, 9,400 kg) but precisely how much we don’t know.
Last edited by RadDisconnect; 14th May 2016 at 05:14.
FBWQuote Originally Posted by haavarla View Post
I’ve seen figures with 4-6% thrust loss for square Nozzle
The F119 has been fitted with SERN nozzle, two-dimensional non-axis symmetric con-di nozzle, and LOAN nozzle. The difference for the SERN nozzle (as would have been fitted to the F-23) was something like 1.5%. The actual thrust vectoring non-axis symmetric con-di nozzle has little impact on thrust, with the caveat that altering the pitch angles does reduce efficiency. Take a look at the SERN nozzle on the F119 fitted to the YF-23, truly bizarre. The SE611, and SE614 variants that powered the two JSF x-planes the asymmetric LOAN nozzle and do produce more thrust, but are different from the F119 in having an extra stage and larger fan.
The studies indicated that the traditional con-di nozzle had a 10% advantage over non-axis symmetric con-di when considering nozzle weight. Then, when the optimal shape ( illustrated by the F119 engines) was compared with cooling requirements, the non-axis symmetric nozzle was within 1% of the standard con-di nozzle.
The major advantage seldom mentioned is that the 2-d wedge nozzle offers a significant reduction in drag. The nozzle is a significant source of aerodynamic drag. The F-111 is a great example of this: the designers chose the nozzle that offered the highest thrust potential (uninstalled), unfortunately the nozzle had a significant performance penalty installed (one reason for the “turkey feathers” on the F100). The 2-d wedge con-di also offered advantages in dry thrust settings.
So, in no simple terms: While the symmetric con-di may be more efficient (ceteris paribus) on a test stand, it is not when installed, especially considering the original studies included a large (up to 600lb) penalty for the non axis symmetric nozzle.
Back to the Pak-fa, why not flat nozzles? Perhaps because the designers wanted thrust vectoring on the pitch and yaw axis, or maybe because they did not want to basically redesign the entire afterburner assembly, jet pipe, for an interim engine.
Last edited by FBW; 13th May 2016 at 13:42.
FBWOpening an F-22 design and discussion thread- to keep F-22 related topics out of PAK-FA thread. Will copy and paste discussion posts over there.
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