kilcoo316I’d question whether he’s the “head of one of the design teams” seeing if he was and commented on that one way or the other it would likely be his job if not his a$$. Not claiming the F-22 has IR suppression (though there are some not so obvious things they could do in that arena) just saying it sounds fishy.
Well – he was asked a clear question on it, and responded with a pretty straightforward answer.
“No, I can confirm the nozzles of the F-22 were not designed with IR surpression in mind”.
Also guys, while not wanting to sound arrogant or anything, I’m working on turbofan engine nozzles at the moment – I can say very clearly, trying to hide an afterburner is like trying to put out a house fire by pissing on it.
The YF-23 tries to hide the initial (NON-AFTERBURNING) exhaust plume from the ground, as does the F-117 and B-2. They try and mix it into the surround atmosphere to reduce the temperature gradients as much as possible.
But the F-22 does not for TVC reasons.
kilcoo316those “tabs/mixers” are called ‘chevrons’.
Don’t worry mate I know 🙂
kilcoo316Read Doug’s statement on having to detect, track, target the SDB. Just because the missile range is 10km or so doesn’t mean it can engage the SDB at that range. The SDB presents a small radar target, meaning that detection is likely delayed, thus extending the whole sequence. This also means that the area of protected space provided by a Tunguska unit becomes smaller, forcing more units to defend a particular area.
Oh please man, think before you post!
We are talking about a multi-layered defense here (and have been pretty much since post #13).
You think that a S-300 or S-400 radar will not detect an SDB at 10km? If so can I have what your smoking?
One thing to consider – if it was judged so effective at repelling air strikes and so cheap as you claimed… why isn’t it selling like hotcakes? 😀
You need all the systems to make it work 🙂
kilcoo316Has a ZSU ever demonstrated it can hit something as small as an SDB?
No idea, but if your putting out a solid wall of rounds, it’ll not take long to hit it IMO.
And where the hell did you come up with 100 kts???
An SDB is a glider… if launched from maximum range I would expect it to be going alot less than 100kts (ground speed) to be honest. If you have information to the contrary, by all means post it. 🙂
kilcoo316Depends on how long the ZSU takes to acquire each target, destroy it, verify its destruction, and acquire the next target. Not sure how firing rate is relevant to the calculation.
How long do you think that would take?
Aquiring targets (especially if slaved to one of the worlds most powerful SAM radars) at 8 kms distance is not going to be an issue, it will be as quick as the computer operates, milli-seconds.
Destroy it… well, depends on the accuracy of the guns I suppose, and its not something I can comment on with a great deal of authority so I’ll leave the floor open for anyone to have their say.
kilcoo316Yeah Right,
I was told it by a head of one of the design teams (for the F-22)… I assume you have a more credible source then? :rolleyes:
next thing you might say that the YF-23 designers have wasted their time as well.
Different aircraft, completely different nozzle design – how can you even begin to compare the two? [Unless of course, you don’t really know what your comparing]
Its and official fact that the F119 employs a LO afterburner.
Its now official… your talking s__t. Tell me how you hide a plume of gas about 1000 to 1300 degrees C exiting 10 feet behind the aircraft?
Its official fact that the F-22 IR signature brings down the detection range from IR sensors to the same level as the Radar would detect it. This actually makes sense.
That is all as viewed from the forward quadrants – by things such as the using the fuel to get heat away from the wing leading edges and drop it out of the heat exchanger half way down the top of the fuselage.
I do believe that the PAK FA will have a round nozzle to take advantage of the 3D TVC but if it looks like anything like that one on the pic (F-22ski) I will laugh my a!s off at their designers for copying again and again the US jets.
What is the point not building on someone else’s research work? Its stupid not to.
First the Mig-1.44 and SU-47 were both heavily influenced by the ATF drawings in the 80s, then they screw them up as not adequate designs: a move in the wrong direction.
Just like the F-15 may have been influenced by the MiG-25 etc etc – you can start those “my dick is bigger than” contests all you want – just shows ignorance really… a common problem will result in similar solutions.
BTW, in your attachment, the F-35 diagram will experience thrust losses from the turbulence created by the inserts/tabs into the nozzle flow. Indeed, depending on just how aggressive they enter the flow, the losses could be quite significant (a few percent at least). Put simply, that diagram is a load of bull****. Having an efficient nozzle of light weight, that can expand the throat area sufficient when in afterburning and generate minimal drag both internal and external are the priorities when designing a military engine nozzle.
Having tabs/mixers etc are for acoustics, and are actually bad for thrust, they are seen on the newer civilian turbofan nacelles [google NASA QTD and NASA QTD2].
kilcoo316Care to point out how you are going to get enough money and manpower so that you can saturate all targets with ZSUs so as to prevent any SDBs from leaking through? Note that the radar on the Shilka is also of very limited range, and it is also not suitable for searching for targets due to its very narrow beam. Putting out a statement like that and feeling smug about it just makes you look rather silly.
“Saturate”?
An SDB comes in at what, 100kts?
If a ZSU radar (or heck, slave it to the radar on the S-400) detects the SDBs 5 miles away [don’t forget, the SDB cannot come in below the terrrain, so 5 miles is VERY conservative] that gives it about 160 seconds.
A ZSU-23-4 can pump out around 4000 rounds in 60 seconds (an example of firing rate – don’t assume that is the only system I refer to). So… how many SDBs do you reckon you’d need to saturate a S-400 battery with a couple of ZSUs in attendance? I’ll leave you to do the maths and look as smart as you want.
kilcoo316Erm… anyone care to point out how an SDB gets by a ZSU?
kilcoo316The scale is approximate.
Uhh, have you scaled them to be the same size in the picture, or is that representative of actual lengths?
Assuming that is an accurate diagram of the PAK-FA (and I still have my doubts bearing in mind the size of the “vertical” fins), then a reasonable conclusion would be dash speeds are a higher consideration in its design than the F-22, with a corresponding lesser emphasis on the wing for low speed manouvering.
kilcoo316Advantages are reduced drag, reduced weight, and lower RCS from side and rear aspects. They will have TVC anyway. Guess it really depends up failsafes and how reliable TVC is, but then when you think that unstable aircraft designs just need to lose their flight control computer and they will crash then it isn’t really that much different.
As well as reduced moments of inertia, and also reduced roll resistance.
But, all such aircraft have triple or quadruple redunancy in the flight control system – and no control surface is moved by a single actuator – more redundancy.
I’m not sure that thrust vectoring technology is mature enough to be used in that manner. The Americans certainly thought the same way, one of the design requirements of the F-22 was recovery from high-Alpha without use of TVC. But, I suppose with the Russians having went through more iterations of developing TVC, they have more confidence in it than me.
kilcoo316With thrust vector capability it is quite likely that the need for control surfaces around the tail might be redundant. This would reduce aircraft weight and complexity and probably reduce RCS as well.
Unlikely mate, I don’t see them building a plane that relies on TVC to maintain stability in flight.
TVC nozzles are working in a very hostile environment, its safer not to rely on them operating for basic flight.
Have read some reports that seem to suggest that the radar used will have 360 degree coverage, ie flat AESA array pointing forwards, sidewards and rearwards, not just as a sensor but also as a RHAWS system and an ESM suite as well.
Early model versions might have the radar of the Su-35BM and many other related systems but full standard 5th gen fighter will probably aim higher in regards to performance.
The F-22 is something similar is it not? Start with a “basic” (yeah, I know, but what else do I say) one-piece AESA, then upgrade to distributed arrays… :confused:
kilcoo316Hi!
An “official” artistic image of PAK FA, from the NPO Saturn, the builders of Al-41:
http://img253.imageshack.us/img253/8775/pakafain3.jpg
😮 😮
Not a chance, the vertical fins are at least 4-5 times too small.
kilcoo316BTw..in all of these pictures the exhaust nozzles are not shielded like the Raptor.Wouldnt that lead to increased IR signature?
The F-22’s nozzles are not designed for IR surpression.
It is like trying to hide the sun! Simply impractical.
kilcoo316In order:
1. DH Mosquito
2. Ju-88
Both of the above were used for more than just bombing, and both were excellent light bombers.
3. Me 262, it was a fighter bomber, while easily the ‘best’ bomber of WW2 in terms of survivability on a strike mission, it never had a chance to make an impact unlike the above two.
4. B-25
5. Pe-2
kilcoo316Of more interest to you ELP might be:
http://www.dailytech.com/Global+Warming+on+Mars++and+Jupiter+Pluto+Neptune/article6544.htm
Global warming was detected on Jupiter last year, and the warming is apparently behind the formation of a second red spot. Global warming on Neptune’s moon Triton has also been noted, with severe atmospheric changes as a result. And even tiny Pluto has experienced moderate warming in recent years, with temperatures rising a full 3.5 degrees.
The common denominator in all these cases, the Earth included, is of course the Sun
I’m always prepared to change my view if the evidence is laid before me. 🙂
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