LmRaptorLmRaptor :
Well , if you believe the LM BS about the “golf ball size RCS” , you are correct đ
The F-22 ‘s RCS is at least 10 times bigger than the BS claim . It is more like 0.001m2 (around -30dB) and even there , I ‘m being hugely optimistic .It is rather easy to prove . đ
In 2006 , the Europeans said that stealthy UAC/UCAVs with an RCS of 0.0001m2 (-40dB) will enter service by 2020-2025 . When one check the look of the UAV/UCAVs and the technologies involved , one will understand that this kind of ultra low RCS was not possible in the early 90s and certainly not for a fighter with a F-22 size . That would mean that the USA have a 30-35 years lead ! đ Soon , we ‘ll learn that they landed on Pluto …
Bluewings believe what you want. But your comparison doesn’t ‘prove’ anything. It can be interpreted in many ways. The way in which you chose to interpret it suits you’re own agenda. It could for example – mean the UAC/UCAV has -40dBsm in a different radar band – one where the F-22 might be weaker. It could also be sanitised or downplayed as it is a speculative requirement at this stage. This in no way proves the F-22 has or hasn’t got a -40bdsm RCS in fire control radar bands.
What is known is that the F-22 has been claimed by numerous sources as having a -40dBsm RCS in the X-band. What is interesting is that even looking at this forum – you will see -40dBsm claimed by people who worked on the Raptor – before the metal marble claim came out. Additionally, Carlo Kopp who has widely publicised anti-F-35 views, ran an open source RCS simulation of the F-35 showing a -35dBsm X-band frontal RCS. F-35 is supposed to be less RCS optimised compared to the F-22. Additionally his model did not take into effect the use of materials/structure/any other RCS reduction methods – it was purely based on RCS shaping. If I were to make conclusions based on that – I would not be surprised if the F-22 has in fact got a -40dBsm frontal RCS in X-band. In fact I would not be surprised if its RCS is a bit better than this.
Finally, for comparative purposes, it was reported in a 2003 special report of Popular Science magazine that the Bird of Prey achieved an RCS of 0.000026 m^2 or almost 4 times lower than -40dBsm. The same report also stated that the next feasible level of VLO could move towards the -70dBsm.
Believe what you want. đ I wouldn’t be surprised if Replica was pretty close to -40dBsm.
LmRaptorWith the same output power but by using GaN (rated at 40-50W 5 years ago) , the RBE2-AA could indeed have a range increased by almost 80% , in the order of 280km for a 5m2 target . Just to say , that would mean that the fighter could track a F-22 @ 60km , if we believe the US numbers on RCS .
You would be right with 60km, if the F-22s RCS was two orders of magnitude larger than what is actually claimed. The reality is, its not.
LmRaptorSenate Panel Barely Turns Back JSF Threat
http://www.aviationweek.com/aw/generic/story.jsp?id=news/asd/2011/06/22/05.xml&channel=defense
By Jen DiMascio
The U.S. Senate Armed Services Committee (SASC) nearly endorsed a move that could end Lockheed Martinâs F-35 Joint Strike Fighter â and the effort may continue.
The committeeâs top Republican, John McCain (Ariz.), sponsored the language, offered during the panelâs markup of its defense authorization measure for fiscal 2012.
The proposal died there on a 13-13 vote before the committee approved the markup last week, but McCain has raised the prospect of trying again later with all senators.
Under the move, if at the end of 2011 the cost of the JSF purchased under the current Lot 4 contract ran 10% more than the target price, the amendment would have put the Pentagonâs largest weapon system on probation. Then, if the program continued to run at a 10% cost overrun one year later, the only money that could be spent thereafter would be to fund program cancellation costs, the proposal stipulates.
âIf this weapon system continues to have horrific cost overruns, as it has, then weâve got to end it,â McCain says, adding that he plans to revisit the idea when the annual defense policy bill comes to the Senate floor. Even then, the Senateâs bill must be reconciled with a version already passed by the House before going to the White House for enactment or to be vetoed.
In separate but related legislative action, the House Appropriations Committee recently approved language that defended the programâs existence in its annual spending bill to fund the Pentagon for 2012.
The SASC marked up its bill weeks after a dramatic hearing on the F-35 program in which Pentagon acquisition chief Ashton Carter told the Senate committee that sustainment costs for the life of the program could total $1 trillion.
At the time, McCain and other senators asked what alternatives the Pentagon has to the so-called fifth-generation fighter.
Nevertheless, instead of McCainâs proposal that would have threatened JSF termination, the committee endorsed different language offered by SASC Chairman Sen. Carl Levin (D-Mich.). That provision tries to get at a similar idea by making the contractor responsible for 100% of any overruns.
Levin says he opposed McCainâs amendment because it applied to the existing Lot 4 contract.
âOn the [Senate] floor, there may be some efforts to apply the pressure we all want to apply to the existing contract,â Levin says. âWeâre looking for ways that we can do it legally.â
The problem both senators are trying to address is that when the target price of the lot increases, the government and the contractor share additional costs equally.
âWe want to stop that. Thatâs the wrong kind of incentive,â Levin says. âWe say set a target price, negotiate it as tough as you can â if you go above that, you [Lockheed] eat it all.â
The SASC vote broke down largely along party lines, but Sen. Susan Collins (R-Maine) voted against McCainâs amendment, saying it went far beyond what she felt was necessary.
â[Defense] Secretary [Robert] Gates has already taken several steps to put the program back on track,â Collins says. âThe fact remains that we need the F-35.â
McCain defends his proposal by saying the country made a mistake in signing the current contracts, because the government winds up penalized when the contractor does not meet the terms of its agreement. âOnly in the defense industry,â he says.
LmRaptorhttp://www.codeonemagazine.com/article.html?item_id=72
Mapping the canopy.
LmRaptorDoes anyone have Rafale thickness to chord ratios
LmRaptorDoes anyone have any thickness to chord ratios for the Eurofighter?
Cheers
LmRaptorIn your Gallic dreams buddy.
LmRaptorCorrect.
If (a very big IF) Eurofighter GMBH lands the contract with the Indian Air Force i am very curious how Lewis Page is going to spin that one out.
I can imagine “The Eurofighter that incredible piece of very expensive shi… just beat head on every “medium” combat aircraft in the planet with the exception of the F35 and the J10 in the most contested export deal for the last two decades, this only proves that the Typhoon is a very big piece of very expensive sh… and the RAF should have bought whatever the Americans are using in their Aircraft Carriers”.
I am eagerly awaiting this.
LmRaptorIt’s a matter of altitude, temp, air density, etc…
That’s why as far as ground speed is concerned, mach 1.0 at sea level is different than mach 1.0 at 40k feet.
Try the calculator at the bottom of this linked page:
http://www.hochwarth.com/misc/AviationCalculator.htmlIn the above Mach 1.53 @ 39k feet it works out to be 540 knots CAS. To get to your Mach 1.22 @ 700 knots you would have to be at 10k feet.
11km-20km alt i.e. 36000ft + which is where you would expect to see the F-35s design Mach 1.6. In this altitude band Mach 1.53 is approximately 907 kts.
T ~ 232.15K
a ~ 305 m/s
V = Ma
V ~ 1.53*305
V ~ 466.64 m/s
V ~ 907 kts
LmRaptora = square root (yRT)
y = adiabatic index (~1.4 for air)
R = (molar gas constant/mean molar mass of air) = ~ 287
T = Temperature in Kelvin
M = V/a
V = 360.11 m/s
For standard atmosphere 11-20km T ~ 288.15K – 56K = 232.15K
a = sqrt(1.4*287*232.15) = ~ 305 m/s
M ~ 1.18
LmRaptorI personally think the comment is as true about the F22 as the 3rd hand story to do with Typhoon and Al Dafrah.
I have recently been told to swallow the idea that people love to talk about beating Typhoon because its so good. This is what he means when he says the F22 would be second for ever.
What comment are you referring to? What 3rd hand story are you referring to? Can you re-explain your second paragraph? I don’t follow.
Cheers
LmRaptorI wouldn’t be surprised about the PAF issue – except it was quoted in one of AFM/CAM… it would have been shoddy reporting to get that wrong.
LmRaptorI would guess he means losing in terms of the overall kill ratio achieved in an exercise rather than losing in a single engagement against a Typhoon. After all the F-22 has lost in single engagements against various aircraft already.
On a related note I read this comment made by a user called khukri on F-16.net which if true certainly casts doubt on the claim that PAF F-16’s gave RAF Typhoon’s a good thrashing …
Yeh but even if it’s based on a kill ratio during a particular exercise its still nonsensical – as it doesn’t place you second best forever. It’s a cheeky and childish little claim. It’s also a pity I can’t quote the view of RAF at Al Dhafra – especially as to why they refused to play with the F-22. All I will say is its like playing with a Bull.
LmRaptorThat’s a bit of a nonsensical claim regarding the F-22. It only has to lose once and then it is second forever. By that logic the Typhoon could have beaten the Su-30/F-15/F-16 once and lost 20 times but those platforms would be – according to him – second forever. I say this as a person who believes the Typhoon has a significant AtA advantage over Su-30/F-15/F-16/Rafale/Gripen in AtA.
His second statement about the F-22 refusing to play is also in direct contradiction to what I have heard from Al Dhafra – where it was the RAF who were offered 1v1 BFM vs. the F-22 but refused to participate as it was considered: ”of negative training value”.
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