lukosSpeicher was shot down by an R-40. Likely an IR version (R-40TD).
http://en.wikipedia.org/wiki/Scott_Speicher
http://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25#Persian_Gulf_War
lukosNo matter how advanced RAM gets, stealth will still be driven predominantly by shaping. True, better RAM will give you more leeway, but EM folks I talked to say that even the best RAM that can physically exist won’t compensate for non-optimized shaping.
I don’t necessarily agree with that. It is possible that one day a skin will be invented which gives zero radar return, in the meantime returns could vary hugely between materials, then you have new developments like plasma. It’s also completely impossible to determine what can physically exist unless you’re God almighty. I’m not saying the EM guy didn’t know his stuff, there’s just simply no way anyone could know enough to make that assertion.
lukosAre you saying the RAM is lower than in F-22 possibly ?
That’s the suggestion. There is almost 20 years separating the designs.
lukosPlaying devil’s advocate here, I remember when the T-50 came out Western ‘official’ comments were based on only photos and they haven’t changed much since. I don’t remember any recent western comments declaring the T-50 as a non sub-par LO design.
Again just playing devil’s advocate …
You can’t estimate RAM though and I did hear somewhere that the T-50 focuses more on RAM than geometry.
lukoslukos
lukosBoth you and FalconDude have displayed disgraceful conduct
Awww, call the ****ing whaaaaaambulance. Or Dr Fedaykin.
For you I’m calling the Failbulance because it’s all you’ve done in this thread.
Look, sunshine,
How many pixels is that then? To what accuracy can we calculate the position of the sun’s centre?:highly_amused:
just because a technique is applicable to astronomy, where I can take a year to gather data if I want, does not mean anything remotely similar can be done in real time in a situation involving lethal weapons. So demonstrate that link/possibility or henceforth hold your peace, capisc’?
I’ve made tons of links but you don’t read, you just blah, blah, blah, this is why you fail so hard – read #1946 – a pixel is not a ‘yes/no’ detector, so your theories fail. Empty cans make a lot of noise!
And for what it’s worth, the Fighter Mafia – including Sprey, their point man in Washington, and I can tell you exactly how far you get without one of those – accomplished great things, and I’d rather lick their salt (whatever the **** that means – is English your first language?) than earn the respect of an ignoramus ITG.
Sprey was an imbecile who wanted an F-16 with no radar. He also was against the F-15, the most successful fighter in modern history.
And isn’t it way past your bedtime anyway?
That only applies to adults in mental asylums, so I can’t see why you’d think that… unless… nevermind.
lukosPAK FU‘s
I LOL’d.
The Russians have made feints at making something similar to Meteor and there’s also some kind of successor to the R-37 I believe. Whether and when these make it onto a 5th gen aircraft is open to debate. The real problem is that against 5th generation aircraft carrying a Meteor-like weapon, a 4th gen aircraft will be killed before it can locate the aggressor, regardless of the AAM it carries. Meteor works for 5th gen launch platforms even better than 4th gen because it increases Pk from outside likely IRST detection ranges.
lukosWhoa, you’ve invented that title yourself? Can I have a shirt with that, please?
So long as you don’t get salt on it.
BTW, few posters (at least me & Jay Langley) have clearly expressed that they found the F-35 unsuitable for the AF of their respective country, due to doctrinal and budgetary reasons.. By providing arguments to support that stance we do exactly what you’ve eloquently put in – proving that the F-35 is bad (for our needs). Nothing wrong with that…
A lot of the arguments I’ve seen have been based on astronomically unrealistic predictions for F-35 cost and an absolutely hopelessly defence of an aircraft that’s 20 years out of date relative to other European competition and hasn’t even been finished yet.
He also made a bunch of false claims, as corrected by others here:
and here:
The fact that you defend such blatant BS-bringers speaks volumes about your own person and intentions here in this thread.
lukosThen why ask the same, again?
What? Go read #1946.
Nice try. Except there is only one poster who has already embarassed himself beyond recognition in this thread and guess what, it isn’t me.
I’m afraid it is. Both you and FalconDude have displayed disgraceful conduct and a very loose grasp on science, whilst also making an arrogant assertion that the range and accuracy of EODAS can be calculated and is poor.
That’s hardly a topic for public domain.. I have serious doubts anyone outside NG knows.
Right so why do we have a guy making assertions that we can ‘do the maths’ on accuracy and range simply because we know how many pixels it has (maybe) and we know the FOV. Can we hell!
lukosThe F-35 is a further development of the X-35. Same concept, very similar design, same company, same project, same design team.
T-50 and 1.44…. Different concept, completely dissimilar design, different company, different project, different design team. They have roughly as much in common as 1986 Porsche 911 Carrera and 2005 Audi R8 – both are German and both are sports cars, that’s all..
I one argued Rafale A vs Rafale B/C/M, I wouldn’t say a thing but this is simply ridiculous.
The X-35 was a demonstrator not a production development vehicle. It’s like EAP/EFA/ACA vs Typhoon.
lukosIt really is sad how this thread has been destroyed by a bunch of fighter mafia salt-lickers with no interest other than to prove that the F-35 is bad.
lukosRead post #1934
Yes, I’ve replied to it thanks.
You shouldn’t copy&paste articles which say things you don’t understand.
So can we expect you to stop posting any links then? The link I copied indicates how it’s possible to attain sub-pixel accuracy with various algorithms. I don’t know exactly what algorithms the F-35 uses but neither do you.
https://en.wikipedia.org/wiki/Staring_array
In radio astronomy the term “FPA” refers to an array at the focus of a radio-telescope (see full article on Focal Plane Arrays). At optical and infrared wavelengths it can refer to a variety of imaging device types, but in common usage it refers to two-dimensional devices that are sensitive in the infrared spectrum. Devices sensitive in other spectra are usually referred to by other terms, such as CCD (charge-coupled device) and CMOS image sensor in the visible spectrum. FPAs operate by detecting photons at particular wavelengths and then generating an electrical charge, voltage, or resistance in relation to the number of photons detected at each pixel. This charge, voltage, or resistance is then measured, digitized, and used to construct an image of the object, scene, or phenomenon that emitted the photons.
Here (at start of article) is an example of what happens at pixel level:
https://en.wikipedia.org/wiki/Position_sensitive_device
The technical term PSD was first used in a 1957 publication by J.T. Wallmark for lateral photoelectric effect used for local measurements. On a laminar semiconductor, a so-called PIN diode is exposed to a tiny spot of light. This exposure causes a change in local resistance and thus electron flow in four electrodes. From the currents Ia, Ib, Ic and Id in the electrodes, the location of the light spot is computed using the following equations.
x=kx⋅Ib−IdIb+Id
andy=ky⋅Ia−IcIa+Ic
The kx and ky are simple scaling factors, which permit transformation into coordinates.An advantage of this process is the continuous measurement of the light spot position with measuring rates up to over 100 kHz. The dependence of local measurement on form and size of the light spot as well as the nonlinear connection are a disadvantage that can be partly compensated by special electrode shapes.
lukosFunny you should mention that……seeing as that ARGENTINA enjoys holding a “Major NON NATO Ally Status”, granted by the USofA…certainly including Argentina into the fold of “Western” in terms of political affiliation….this is the SAME status that is enjoyed by Australia, New Zealand, South Korea, Israel, Japan and Egypt…..OH my, that does seem to be almost a complete list of F35 “customers”…so I guess that for all , inclusion into this catagory is good enough ……at least to sell the USA’s “Most advanced weapon” too anyway…….
Brazil maintains and enjoys pretty decent ties with the west and with the USA as part of the G8+5….their political allegiance with BRICs is an obvious issue…but in all cases, it seems Brazil treads a fine line between situations and stances anyway……
I do hope that your incorrect opinion is again of note…..
and just to add, by your equation , the Rafale’s that where involved in an mid air collision WHILE flying in formation has anything to do with targetingor even radar issues?…..they where within visual sight of each other………..WHERE on the other hand, the Typhoon II couldn;t locate, identify and conduct evasive manouvers prior to having a mid air collision with a LEAR Jet?………strange that isn;t it?……..
By the way, is there any write up on this event?…I would certainly like to see some documents that outline the timeline for the repairs to active flight that occured for that Typhoon II………especially as I had understood that the damage done was highly significant….
OMG, you’re one of those people who thinks it’s appropriate to include dots in their post. I bet you eat glue and lick salt too.
The US struggles for allies in South America but a pat on the back still doesn’t make Argentina economically or politically western. There’s having a large GDP and having a large GDP/capita – two entirely different things.
The Learjet was flying outside the Typhoon right next to it and in a turn it flew straight into the belly of the Typhoon. The Typhoon survived because it’s a good solid aircraft, the Learjet died. Face facts, 5 losses in <100,000 flying hours with single home nation use for the Rafale, vs 2 losses in >250,000 flying hours, with 7 nation use for the Typhoon. To put things in perspective, the RAF have had no losses or accidents in >100,000 flying hours with Typhoon. Speaks for itself. Stop trying and stop dotting.
http://www.kantipurvideos.info/plane-crash-in-germany-learjet-and-eurofighter-typhoon-collides/
According to Spiegel, the Learjet, which was carrying two people, was sent into a tailspin after colliding with one of the Eurofighters as both aircraft turned to the left.The military jet sustained damage but managed to fly back to its base in Noervenich, near Cologne, where it landed safely. Focus, a German online news portal, reported that the two aircraft’s wings crashed into each other fuselage.
After a mid-air explosion, debris from the Learjet fell into a wooded area near the town of Olsberg, with some parts falling just 80 metres from houses.
Authorities located the plane wreckage and found the body of one of the passengers. The other is still unaccounted for.
A spokesperson for the German air force said it was a routine exercise and the reasons for the crash remained unknown. An investigation is under way to look into the causes.
lukosMC, right you are, diffraction. Pre-first-coffee post. However, I think you get what I was trying to tell Lukos. You’re seeing flare and aberration in that image, probably affected by video-to-still conversion, however that was done. It looks normal because flare and aberration are most apparent with bright light sources, and a rocket in IR is… petty damn bright.
However – Contax/Zeiss… I am obligated to burn you at the stake as a lifetime Leica shooter.
If the light from a distant point source (such as a star) enters a lens, it will in theory be focussed on only one pixel of the focal lane array, but Seidel and other aberrations may cause some light to spill onto nearby pixels. My nearest friendly lens designer spends a lot of time trying to hold those aberrations to a minimum.
BTW LowObservable, he also keeps diffraction to a minimum. In your posting 1906, I suspect you meant ‘refraction’.
That’s what my old Contax has been doing since the mid-1930s, and many cameras in the half-century before it was built.
If my memory is correct, the lens designer’s rule of thumb is that by the time an object is 1,000 times the lens focal length distant, that object is effectively at infinity.
So for my 5cm focal length Sonnar (a lens as old as the camera, so hardly state of the art), anything more than 1,000 x 5cm is at optical infinity. Let us be pernickety about the degree of sharpness we require, and go up an order of magnitude in that numerical factor of 1,000, at which point anything at a range of 10,000 x 5cm (=500m) is at infinity. So it will produce sharp images at the ranges likely to be experienced in real-world air combat.
So we can explain why an image on a 1024×1024 pixel detector at 800nm occupies several pixels and is round on magnifcation and not square. The aberration is actually processed and can be used for useful information.
It is also possible to attain sub-pixel positional accuracy.
http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1737844
The star’s centroid plays a vital role in celestial navigation, star images which be gotten during daytime, due to the strong sky background, have a low SNR, and the star objectives are nearly submerged in the background, takes a great trouble to the centroid localization. Traditional methods, such as a moment method, weighted centroid calculation method is simple but has a big error, especially in the condition of a low SNR. Gaussian method has a high positioning accuracy, but the computational complexity. Analysis of the energy distribution in star image, a location method for star target centroids based on multi-step minimum energy difference is proposed. This method uses the linear superposition to narrow the centroid area, in the certain narrow area uses a certain number of interpolation to pixels for the pixels’ segmentation, and then using the symmetry of the stellar energy distribution, tentatively to get the centroid position: assume that the current pixel is the star centroid position, and then calculates and gets the difference of the sum of the energy which in the symmetric direction(in this paper we take the two directions of transverse and longitudinal) and the equal step length(which can be decided through different conditions, the paper takes 9 as the step length) of the current pixel, and obtain the centroid position in this direction when the minimum difference appears, and so do the other directions, then the validation comparison of simulated star images, and compare with several traditional methods, experiments shows that the positioning accuracy of the method up to 0.001 pixel, has good effect to calculate the centroid of low SNR conditions; at the same time, uses this method on a star map which got at the fixed observation site during daytime in near-infrared band, compare the results of the paper’s method with the position messages which were known of the star, it shows that :the multi-step minimum energy difference method achieves a better effect. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
The point I’m making is that positional accuracy determination isn’t simply a matter of X degrees FOV divide Y pixels. This is also why the processed image is not a square dot.
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