MigLI guess the large size of the Nimrod or Atlantic are certainly more confortable for the extended patrols which they undertake. But I still think it would make sense for a country like Italy which only needs to patrol that shallow, big lake called the Mediterranean sea.
MigLYou are absolutelyright, no one would buy an upgraded F-104. We are just ‘dreaming’ out loud here.
MigLThat would involve total re-design of the aircraft ala F-20, which no-one wanted in 1980, because they would rather have F-16s. I don’t know if you remember the F-16/79, an early F-16 with the J-79 engine of the F-104S, which, at altitude, had similar performance even though its engine was rated 6000 lbst less at sea level (again no-one wanted it since, when Reagan succeded Carter, he was willing to sell ‘real’ F-16s to anyone). An F-104 with a 22000 lbst M-53 could probably do M2.8 and easily zoom climb to 100,000 ft. That’s MiG-31 territory, isn’t it?
MigLAt the time of ‘peace’, during the cold war, the nimrod’s task was patrolling the north sea for Russian deep diving subs. At this time of war, the Taliban and other terrorist forces don’t have subs under the sand, so …
That being said, why did Britain need such a large aircraft, and all the rest as well such as P-8, P-3, Atlantic, etc? The US Navy used the tiny (in comparison ) S-3 for ASW,and last I heard, was giving them away to friendlies. Would it not have made more sense to take two dozen and upgrade them instead? Also, given the recent close ties with Italian defence contractor Finmeccanica (Agusta/Westland, Eurofighter and I forget the name of the joint electronics system company), and the age of Italy’s Atlantics and the need for a replacement (France upgraded theirs and Germany bought more and less ambitious upgrade), why not a joint S-3 upgrade to lower costs even more?
MigLBecausethe M-53 is technically a ‘leaky’ turbojet with a low compression ratio. This means that its dry SFC is poor, but its wet(afterburner) SFC is good, which is bad for cruise range. We aren’t looking for range in a point defence interceptor. The problem with afterburning turbofans (even low by-pass) with high compression ratios is that they quickly loose thrust with altitude and are limited in speed by compressor heating ( intake duct compression due tospeed adds to static compression ). This is why an F-16 is limited to M2, its F-100 engine hah compression in the mid 20s, and Rm-12, Ej-200 and M-88 even higher. The Mirage 2000, with M-53 of compression ratio about 10:1 (not sure exact number), is cleared to M2.5. Neither plane is drag limited, but the F-16 is engine limited.
Have you ever wondered why, since the 70s, when turbofans with ever higher compression ratios, started to become the norm, maximum mach number started to decline and level off at about M2 when a lot of earlier ‘century’ fighters such as F-104, F-105, F-106 along with F-4 could do M2.3 to M2.5. The F-8U-3 was reprted able to do M2.8 to M3 with the same engine as the F-106 anfd F-105.
MigLNice idea as I like Starfighters, especially the S-asa version used lately by Italy. However you would probably find that the F-100 engine would need much greater airflow and considerable re-design of intakes and ducts. You would also find that its high altitude acceleration and speed would decrease considerably, see British, Spey-engined Phantoms as an example. A better engine match would be a 22000lbst M-53, which would improve the F-104’s best qualities (climb rate, acceleration, hi-alt performance) and make it the best point defence interceptor in the world.
Another argument against is the fact that there are tons of F-5Es which have modern upgrade programmes and easier maintenance obligations than F-104s, but nobody wants themas it as cheaper to buy surplus American F-16s. A shame,really.
MigLI haven’t always agreed with COLA’s views, but on the subject of the F-111, I have to agree with him. The fact remains that they are old, maintenance intensive airframes which could be outfitted with state-of-the-art modular electronics to reduce some maintenance, they certainly have the room, but it’s more cost effective to replace them to save on all other maintenance costs. In terms of capability, I agree that they are unmatched to this day. One thng I disagree on, at LOW LEVEL, there is no other aircraft that can keep up with an F-111, not even EF or F-22.
MigLI almost fear to tread into this highly polarized argument, but the solution is quite simple. Obviously the French on the one hand, and the British,German Italian and Spanish on the other should not be included since they fund the projects, but, in terms of export sales to other countries, who has sold more? I don’t think Defence Ministries in these countries care about Jon Lake’s biases, they simply test the aircraft and judge which will give them the ‘best bang for the buck’, and as far as know EF has outsold Rafale both in number of countries and total numbers.
MigLConsider a single beam of EM radiation, say light to make things simple. We pass this beam of light through two slits. Now we have two beams of light exactly in phase. Diffraction or interference depends on the phase as well asthe path length, and What do we find? It turns out that where the path length is eqivalent, the beams re-enforce (amplitude addition) and where the path length differs we get cancellation (amplitude subtraction). This gives rise to the classic double slit interference pattern which was originally demonstated by Young (I believe, it’s been a long time since GRADE TEN PHYSICS, but I’ m sure you can GOOGLE this classic experiment if you didn’t study science). This shows that where the beams are out of phase, whether by path difference or initial emission, the beams cancel and where in phase, they add. Incidentally Over G, it was also in grade ten that I learned about wave/particle duality of EM Radiation. Don’t forget to consider both ‘mathematical models’ when considering aspects of light’s reality.
MigLSign, if a radar picks up a return for few seconds before that return disappears, how can it track the target? Cancellation doesn’t have to be immediate for it to work effectively. We also consider that the emitting radar also has to process the return before it can designate the target so the process doesn’t happen at the speed of light.
Over G I have a BSc in physics and can tell you that EM waves can be cancelled and the diffraction you are talking about would be below the noise floor and be diregarded by the emitter radar, remember signal strength falls with the square of the distance so the target has a four times stronger signal to work with than the emitter. One of the current RAM techniques is not just ferrite beads suspended in paint but two reflective surfaces separated by one quarter wvelength of the incident radiation giving an amount of cancellation at (unfortunately) only one specific wavelength. You can already buy noise cancelling headphones for about $50, the technology is that simple with modern signal processing and would have been science fiction 25 yrs ago, roughly the era of the electronics in the space shuttle (intel 80286 design rules). The electronics of the F-22 are slightly more advanced but still about 20 yrs vintage (intel 80486 design rules). Can you predict what transistor integration will be possible in another 25 yrs?
MigLThis board seems to re-hash the same arguments over and over. Over G doesn’t seem to understand stealth and the closest to understanding is Sign since he realises that its an evolving technology which is still in its infancy. The way I see stealth evolving is away from geometric, typified by the F-117 and more and more towards electronic. I don’t mean ECM where the signal is drowned in a sea of noise, but towards active cancellation. The theory is simple; a computer analyses ALL incoming radiation and emits an inverse wave therby creating destructive interference and zero reflected signal. This is still science fiction, mind you, but at the rate electronics are advancing, eventually a 747 could be made invisible to radar, and given fast enough processing and on-board lasers, even optically invisible. The point to remember is that it is a tool that is constantly evolving with technology and as defences are developed to make the current tool obsolete, the tool itself is developed further to increase its usefulness.
MigLI guess my previous post wasn’t clearly explained. Wing design is a part of the design criterea but not the only one for avoiding the transsonic drag hump. The total package is much more important as evidenced by the fact that the Convair F-106 does M2.35 while the F-102 is subsonic and the area ruled F-102a does M1.2 with the exact SAME WING. Same thickness/chord ratio, same aspect ratio, same sweep angle and same profile.
As to the limiting Mach number, the Mirage 2000 and the MiG25-31 are limited by aerodynamics, as is the SR-71 and many earlier generation planes (f-104, f-106, F-4, ee Lightning, etc.) because they use low compression engines. Planes like the f-16, f-15 and newer use high compression engines (>24:1 comp. ratio) and are therefore engine limited to about M2, the importance of t/w ratio and sfc being way more important than time spent above M2. The m53 is technically comparable to a leaky J-79, nothing more.
I guess if you reply to select sentences instead of ideas it’s very easy to argue a point. If you disagree with one person, there’s a 50/50 chance you are right; if you disagree with 20 persons, chances are you are wrong. Remember, arrogance is a poor substitute for knowledge.
MigLMr Dare2 only considers wing sweep a determining factor for critical mach number and top speed; there are numerous other factors. It wouldn’t take ten years to refine the design of a modern combat plane if it was that simple. The top speed of the MiG-25/31 and even the Mirage 2000 has been brought up but the limiting factors in these case are not aerdynamic but engine related. A high compression engine like the one in the f-22, f-16, Eurofighter and even Rafale is limited by compressor heating, the MiGs and M2000, having lower compression turbofans or even turbojets are not. As for critical mach number, the Convair f-102 had the same wing as the F-106 yet the f-102 wasn’t even supersonic while the F-106 did m2.35 and only after the Whitcomb area rule modifications did it reach m1.2. There are other factors to consider.
MigLThe f-111 was a great choice for Australia’s long range strike, but like all complex planes of the sixties, has become a maintenance nightmare. It did not cause the cancellation of the TSR-2, that blame belongs to British politicians and armed forces. The F-111 is still a credible strike platform but for the maintenance issue. It has been written in IAPJ that a squadron of F-111, flying at 200ft and M1.25 could have devastated Baghdad without dropping a single bomb; the sonic boomswould have done more damage.
MigLSome people on this forum don’t realize that radar is an E-M wave which can be reflected, absorbed, scattered, diffracted, destructively interfered, transmitted (in different directions) and even actively cancelled. Super computers are needed to optimize these oten conflicting effects to minimise RCS. Shaping for stealth is rather simplisic and ineffective.
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