that engine turns off its turbojet portion at a lower speed than mach 3 and converts to a ramjet mod. bypassing the turbojet stages
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The F-12 interceptor design concept that competed against the F-106X featured a nuclear tipped missile to be used against enemy bomber formations. The F-106 already was equipped with it: one Genie missile was nuclear armed. Along with, it carried four Falcon AA missiles. The idea was to fire the nuke missile into the bomber formation, depending on the EMP to blow out the electronics of the bombers, dosing the crews, and forcing them to turn back.<br /><br />All the interceptors of that era had internal weapons stores: engine thrust was still nowhere near current day standards, so aircraft exteriors needed to be very clean aerodynamically to fly supersonic. The F-102 couldn't go supersonic until its design was area ruled. The prototypes couldn't go SS even on full AB.<br /><br />The 106, though, went as fast as mach 2.39 with its standard configuration and wing tanks, still the fastest single engined aircraft in history, and at the time the fastest production aircraft before the Blackbird came along. McDonnell cheated with the F-4: they stripped it down and installed an MIPCC system (nitrous oxide injection) to make it beat the Six's record.
Well, americans saw a couple of them flying at mach 3,2 over israel in 1973. Consider also this. Mig 25 is capable of M2.83 with 4 R-40 huge missiles under its wings.<br />Its actually E(Ye)-266M, a prototype which led to the development of the 31, that set those records.<br />Funny to mention it is FASTER then yf-12 with payload on closed circuits.<br />No structural damage was ever done to those MiGs that flew over Mach 3.2 .<br />Americans later told that when flown at speeds greater then M2.83 the engines would overheat and burn up, and they suggested that this was the case with Migs in 1973. Funny to say that since all of those migs safely landed. How, if their engines were burned up? I don't belive you can glide a 50 ton Mach3 plane for such distances.<br />One thing I can believe is that the M2.83 limit was mainly set because of the profile of the pilots that flew on MiGs. Over 1000 Migs25/31 were produced, and with such large numbers, its probable that not only the best pilots would flew this birds. So they limited it to M2.83.
a list of confirmed MIg 25/31 performances<br /><br />-OKB MIG-Butowski, Miller: <br />"The Israelis and western observers tracked it at 3,2 Mach."<br /><br />-MiG-25, Gordon:<br />"It achieved 3,2 Mach (3400km/h) over Israel without causing airplane damage."<br /><br />-Pilot ,magazine, may 1998:<br />" Has been tracked over Israel cruising at 2,8 Mach and at least one time<br />hitting 3,2 Mach."<br /><br />-Air Forces Monthly, June 2005:<br />"The Indian AF MiG-25 has 3,2 Mach max speed and 88,600 ft ceiling."<br /><br />-MIGS-Belyakov, OKB MIG chief designer:<br />"The speed of over Mach 3 can be reached without causing a damage to the aircraft and there is even no need for inspection after such flights."<br /><br />-Modern air combat,Gunston,*****, 1983:<br />" OKB MIG settled for 2,8 Mach in combat version and 3,2 Mach in clean condition."<br /><br />"The MIG-25s speed of 2,83 Mach (3000 km/h), is somewhat theoretical, lateral stability and life time were supposed to diminish beyond 3000 km/h, but number of pilots exceeded Mach 3 without damaging the aircraft or sending it to obverhaul shop to checking."<br />airframe life time and lateral stability supposed to diminish, not <br />went to unacceptable level.<br /><br />"The MIG-25s over Egypt exceeded Mach 3. After landing there was no problems whatsoever."- MIG-25,Gordon,Putmakow, 1994<br />
Keep in mind that published maximum speeds of fighter aircraft tend to be fictitious: while our info on the Mig-25 said it could go 3.2 mach, and had, official Soviet publications stuck to 2.8. Similarly, the US F-15's official published max speed was 2.5 mach, but as I worked on them, I can personally attest to the fact that I'd seen them come back with the mach meters pegged at 3.2 on several occasions when interception missions were done (i.e. there are two needles on the mach meter: the variable one, and one that the variable pushes upward which stays in the max position reached to indicate the fastest speed reached in that flight after landing when flight records are completed and maintenance write ups are dealt with).<br /><br />Fact is that the F-15 could kick the Mig 25 all over the sky in dogfight conditions and its missiles were more reliable and harder to dodge than the soviet AA's. The Eagle had been flown against captured migs, and I can attest that in our own exercises against US Navy F-14 topguns, the Eagle was superior in a dogfight, and we'd mop them all week long, til the last day when the squids were permitted to use their Phoenix missile systems: we'd be dead before even entering the combat area, so much for dogfighting.<br /><br />Any time US fighters have gone up against Migs, the migs always lose between 5 to 100 of theirs for every one of ours they manage to nail (typically depending on an unlucky equipment failure or SAM damage to even the field).
OK, I'll bite<br /><br /><br /><br /><br /><br />I've been over this discussion about a million times. But I don't believe a thing about the F-15 going Mach 3. For simple reason of the airframe, most of it aluminium, can't withstand the fraction. Hell, the only reason the Blackbird was made the way it is, is because of the friction. So sorry, even though you claim to work with them I have very little faith in it. (Neither do I believe that MiG-25s can reach such high speed without damage)<br /><br />Besides, energy is the name of the game during aerial combat. Any MiG-25 pilot that gets itself into a dogfight screwed up royaly. A MiG-25PD with look down -shoot down is supposed to stay for away and use R-40s to try and get its enemy, as soon as something comes close its supposed to cut and run. The MiG-25 is by no means perfect, it got nailed in the Iran-Iraq war even by a F-5. I believe the MiG-25 got about 6 or 7 confirmed kills in the Iran - Iraq war, mainly Phantoms.<br /><br />Ah well, if you would be interested in that, you can check this: http://www.acig.org/artman/publish/cat_index_15.shtml<br /><br />Fact is that a MiG-25 was captured but returned, and after that all MiG-25s were upgraded to PD standard. No MiG-25 flew actual DACT missions against US fighters in training. Only MiG-21 and MiG-23s. And good pilots flying interceptor planes keep distance, dogfighting is for other aircraft. Off course a F-14D is going to use the Phoenix, and off course the MiG-25 will use R-40s. Thats their strength.<br /><br />The MiG-31 was never tested in actual combat, which is a good things since only Russia and Kazakstan have them. It wouldn't have been pretty if they were actually used. But its a whole different aircraft, first electronic radar, and better AA-missiles.<br /><br />
Nose cone tip, leading edges, and many other areas of the F-15 are titanium, as are some areas of the engine cowling and airframe members. 25.8% of the airframe is titanium. "most of it concentrated around the engines and in the inboard sections of the wings. The three main wing spars and the bulkheads connecting them and the frames of the engine pods are of titanium. Aft of the forward main wing spar, the fuselage skin is also of titanium. The cantilever booms outboard of each engine which carry the twin fins and horizontal stabilators are made of titanium, as are the stabilator attachments and the spars of the fins. There is a titanium firewall between the two engines to prevent a fire in one engine from spreading to the other. "<br />http://www.csd.uwo.ca/~pettypi/elevon/baugher_us/f015.html<br />http://www.faqs.org/docs/air/avf15_1.html<br />http://www.aerospaceweb.org/aircraft/fighter/f15/<br /><br />BTW: What makes you believe that mach 3.2 was the maximum speed of the Blackbird? It needed to be all titanium because it would fly the whole mission at that speed, with the airframe acting as a heatsink. The F-15 of course doesn't have supercruise capability, so it was certainly confined to short bursts of supersonic flight as were all pre-F-22 aircraft outside of the Blackbird.<br /><br />I've certainly seen planes come back with paint stripped off them in places from the speed.
yes you got the gist of my brief statement. I am well aware of inlet unstart. it is the reason that the Concorde does most of the shocking down (compression)outside of the inlet area avoiding the probability of putting Granny on the front bulkhead or having to wear 5 point harness' on an airliner. It is more efficient to have the airflow totally compressed within the inlet housing. <br /><br />and no I meant at a lower speed than mach 3 as in a speed less than mach 3 the ramjet would come into effect.
Blackbird speed is limited by the temperature of the engine inlets and their max temperature of 427 degrees of celsius.<br />Can the aircraft go faster? Yes, provided the temperature limit is not exceeded. The flight manual even states that Mach 3.3 can be authorized under those circumstances. That'd be Section V, page 5-8<br /><br />About the f-15 top speed...well, officially it's M2.5. I don't think it could go as fast as M3.2. Blackbird had troubles stayin that fast, and it was built for speed.<br /><br />My uncle used to work for Yugoslavian air forces as an engineer back in the 80's. He had similar stories about Migs 21 going M2.4. To this day we are still fighting about this. The truth is that indicated airspeed may differ from true airspeed, atleast with Migs-21, but he's still convinced about this. <br /><br />Mig 25 was seen on radars going M3.2, and routinely cruised at M2.8. Those are the facts. The thing I find unbelivable is the ability to fly at M2.8 while fully loaded with R-40 missiles, and that makes a huge drag. <br /><br />Because of the variable geometry inlet that the Mig-25 posses (F-15 also have one), the pressure difference offered by the shock wave is very significant to the inlet suction zone. Since the area of the Mig-25 inlet is much much larger than F-15's and the design shock compression is for higher speeds, the Mig-25 has much more thrust at high supersonic speeds. Bottomline, the Mig-25 has better high speed performance than the F-15. Now, cnsidering this, its not probable that a f-15 would do M3.2 if a Mig 25 was at its best there.<br /> <br />here's a text I found while serching for Mig combat records<br /><br />Gulf War Experience - ----------------------------<br /><br />Did you know that a MiG-25PD recorded the only Iraqi air-to-air kill of the Gulf War? It dropped an F-18C on the first night of the war--then went on to fire another missile at an A-6 and buzz an A-7, all while avoiding escorting F-14s and F-15s. <br />An isolated incident? How
My F-15 unit was a NORAD unit, so we were partnered with the NW Air Defense Sector, and shared dorms with all the 'scope dopes' that watched all the radar screens for the northwestern US and western Canada. They frequently spotted our guys flying over specced speeds, as well as other 'vehicles' flying at so-called 'impossible' speeds and were generally told to ignore them since they checked out on IFF. At the time, the Cold War was on, and the USAF kept the true airspeed of its interceptors classified for obvious reasons that they didn't want Soviet bombers to know how fast they could really be intercepted in time of war. There is also a numerical interest in optimizing the lifetime of the investment of taxpayer dollars inherent in a lot of MOOs one uses in the US military. USAF planes delay dropping the nose on landing in order to reduce wear and tear on the landing gear and brakes. Speccing low maximum speeds and turn rates extends the lifetime of the airframe. Maxing out an airframe in peacetime is a waste of tax dollars, save it for a real war when the nations survival is at stake.<br /><br />Indicated airspeed is actually always less than actual speed, particularly at altitude, since IAS is based on air pressure. You can fly at an IAS of only 350 kt while going mach 3 actual if you are at the right altitude (that is in the neighborhood of 70kft for this particular datum).<br /><br />As per inlet size: this isn't quite the indicator one thinks. While it can specify the maximum possible thrust of the afterburner, it is also dependent upon bypass ratios, AB compression ratios, and other factors, such as vehicle drag (more drag means more thrust needed, that big fat nose cone on the Mig-25 means a helluva lot more cross sectional area, and the plane just isn't as clean as the F-15), vehicle weight (the T/W ratios of those Tumansky turbines is not great, the generators are huge in order to power that big heavy radar, and the rough airfield landing gear means lots of use
I'll add two cents and sinc you seem "kinda on the ball" ask a question<br /><br /><br />First somewhere you said that the F-22 was the first to sustain supersonic flight. Its true that it can sustain supercruise, ie without afterburner. But the MiG-31 had a supersonic radius of up to 500nm on internal fuel capacity, all the way going Mach 2.35. The foxhound was well capable of sustained supersonic flight for quite a long time. But supercruise is a neat feature, nothing new however, even the Lightning could do it.<br /><br />The question I had was about inlets, I always had the (foolish maybe) idea that the inlets were one of the most important limiters to theoretic max speed. For example aircraft with fixed inlets have trouble breaking the speed of sound altogether because of supersonic shockwaves entering the engine. And aircraft like the MiG-25 with normal varaible inlets could sustain Mach2 speeds, but when going into the higher mach regions the inlets would not slow the air down enough. Which results in the overspinning of the turbine. Is that correct or does the intel configuration have nothing to do with max speed?
And aircraft like the MiG-25 with normal varaible inlets could sustain Mach2 speeds, but when going into the higher mach regions the inlets would not slow the air down enoug.<br /><br />That is one of MiG-25s secrets behind its performance. Its R-15 engine has thin bladed transsonic compressor with low static presure and impulse type single stage turbine.<br />That enabled Mach 3 speed, but without airflow drawbacks and vices of mixed compression engine of Blackbird family.<br />It also had, I think, some 500 liters of alchohol used for cooling
For cooling of the radar only. The Saphir radar was so powerfull that it could burn through most of the ECM, only problem is that it was not very stearable and could only engage a single target. To cool the radar and its "computer" alcohol was used.
Yes, I know about the radar. But I was always under the impression that 500 liters was really too much, especially since the radar wasn't turned on always. I figured that it may have other cooling assignments, like wings or engines.<br />I believe that one of the reasons why soviets didn't use transitors at the time was exactly the temperature of the aircraft at those speeds(not the nuclear EM pulse threat) and the additional weight of the cooling system for transistor based electronics.<br /><br />What about Avro Arrow. It was a fascinating plane. Too bad those orenda engines never flew in the actuall arrow. With J-75s, Mach 1.98 was reached. It also had a weapons hangar, which would be perfect for storing the rocket. I wonder how big was that dropable weapons bay?
Until the F-22, the only plane that could achieve supersonic without afterburner IN LEVEL FLIGHT and keep it, was the Concorde. 500 nm of supersonic flight isn't much. The F-15 could fly 3500 miles at high subsonic with wingtanks capable of supersonic flight. "Supercruise" means having a supersonic range not significantly different from subsonic range, which primarily means high thrust to weight, no need of afterburners to attain and keep supersonic speeds, etc.<br /><br />The Lightning was a lot of things, but not that. Certainly not built for range, it was built to intercept and climb high. A great plane.<br /><br />Inlets are one of the important limiters to theoretic max speed. The F-106 is an excellent example of this. Essentially started out as the F-102B. The 102 couldn't go supersonic until the area rule was discovered and applied, which is the difference between the YF-102 and the F-102A. The 102's engine was underpowered, its weapons system was a poor substitute for the planned Hughes MA-1. The F-102B was to have better inlets, more fuel capacity, and the MA-1. It became so modified it was redesignated the F-106. It still had inlet problems, limiting its speed. The next gen 106, the F-106X had rectangular variable inlets like the F-15 and Mig-25, and Convair claimed it would go mach 5. It beat the YF-12 in the interceptor competition on paper, but both were cancelled by Robert "Mack the Knife" MacNamara.<br /><br />Up to mach 3, the major problem is that non-variable inlets let in too much air the faster you go, and it hits the engine at supersonic speeds. Since the airfoils of the compressor blades are not supersonic capable, they automatically create too much bowshock drag and they unstart. You use the variable geometry to choke off the air going to the engine, to slow the air down, but this limits the amount of air the engine receives. It thinks it's operating at a higher altitude (lower pressure due to expansion after the choked inlet) so its oxidizer limite
The Arrow would have made for an excellent launch platform. A Mach 3.0 version (Arrow Mk 3) was on the boards at the time of the cancellation. Only five of the Arrow Mk 1 were produced... they were the J75 'underpowered' prototypes that topped out just over Mach 2. The test pilots were under instructions to not surpass Mach 2 until they were flying the Iroquois powered Arrow Mk 2. The Iroquois engine that was intended for the production aircraft was significantly lighter than the J75 and had 40 to 50% more thrust.<br /><br />The weapons bay was large enough to hold the Sparrow, so that should give some idea of the size. I've been next to a full-size replica (for a full-size replica Arrow) and it is surprisingly large. Even if the booster was too large for the internal bay, it would have been fairly easily carried in a conformal configuration due the the clearance between the bottom of the aircraft and the ground. The Arrow was designed with the ability to carry an external fuel tank behind the weapons bay so I'm guessing a booster on the order of 35' in length and 2.5' to 3' would have been possible dimensionally. Judging from the empty and gross wgts for the prototypes, I don't think a payload weight of 15,000 would be within reason.<br /><br />Often overlooked, the Orenda PS13J Iroquois was a marvel of gas turbine design and at least a decade ahead of the competition. The loss of that engine is at least as sad as the loss of the Arrow program. Other countries were interested, probably most notably France, for use in the Mirage.<br /><br />The engine was flight tested on a B-47B loaned from the US Air Force. After the flight test program, the B-47 was returned to the US Air Force and scrapped. According to this source, the airframe was actually bent due to the tests.<br />http://www.bigpedia.com/encyclopedia/B-47<br /><br />It's a damn shame the project was cancelled.
I'm pretty sure the underpowered Arrow prototypes could supercruise. One was still accellerating while climbing at Mach 1.96 while only in intermediate afterburner on the underpowered J75 model during flight test.<br /><br />I have also seen accounts from F-104 pilots that they could cruise just over Mach 1 without afterburner if they were clean. <br /><br />The F-22 may be one of the first deployed fighter that can do it well enough to make it operationally useful in a combat situation, but I wouldn't say it's the first to have the capability cruise beyond Mach 1.0 without afterburner.<br /><br />Edit:<br />I found this source for the supercruise capability. He states that the F-104 had the ability to cruise at M1.1 on military power. <br />http://www.dcr.net/~stickmak/JOHT/joht12f-104.htm
"military power" IS afterburner. <br /><br />Cruising while unloaded just over mach 1? shiver me timbers. But they couldn't get over the mach 1 hump without afterburners, as I'd said. "Supercruise" status requires the following:<br /><br />a) the ability to go through the sound barrier w/out afterburner<br />b) the ability to sustain a supersonic speed without afterburner<br />c) the ability to do so for an extended period such that one can fly one's normal range, or close to it, while on supercruise, carrying one's normal load.<br /><br />If you can't do these things, it isn't 'supercruise', its just a minor sweet spot in one's flight regime when your plane is stripped down, or faking it while burning a lot of fuel up trying to keep up. Equivocations abound, such as the F-4 Phantoms 'breaking' of the F-106's speed record, the six did its record with a stock aircraft. The Phantom had to be stripped down and have MIPCC installed to beat the six on the speed course, and the six only had one engine to the phantom's two.
"B-52s, L-1011, 747, and others are all limited to carrying either off center in an underwing position, or on the dorsal side, with all its operational problems."<br /><br />Funny, that L-1011 sure looks like it's using a centerline launch position to me.<br /><br />http://www.orbital.com/SpaceLaunch/Pegasus/
My understanding has always been that full military power is the highest power setting before you go to afterburner (or reheat if British). It may have crept into my vernacular while going through non-augmented gas turbine design. My mistake. I should have said 'maximum dry power'. <br /><br />I used the word 'clean', not 'unloaded'. Two very different meanings aerodynamically. While I can't find a reference that explicitly states it, my understanding was that the F-104 COULD pass through Mach 1 without requiring afterburner. I would agree with you about the sweet spot, though: this would likely only be possible within a fairly restrictive altitude and temperature band.<br /><br />Using that definition, Concorde (and certainly the Tu-144) were not supercruisers either. Both required afterburner to pass through Mach 1. Concorde operating practice required the use of afterburner from around 0.95 through to 1.7.<br /><br />Let me change the semantics a little, then: while the F22 may be the most capable "supercruise" aircraft flying, it is certainly not the first aircraft that has had the ability to cruise supersonically without the use of afterburner.
Let me revise and retract my former comments. Wikipedia seems to have documented this supercruise issue well.<br /><br />http://en.wikipedia.org/wiki/Supercruise<br />"Note that of these aircraft, only the civilian Concorde and Tupolev actually spend most of their cruising time at supersonic speeds, and that many of the fighters listed can only marginally exceed the speed of sound without afterburner and may only be able to do so without an external weapons load. The F-22 Raptor and Eurofighter Typhoon's supercruise capabilities, by contrast, are touted as a major performance advantage over other fighters....Another special case is the SR-71 spyplane. This aircraft's engines were designed for sustained and efficient operation at supersonic speeds using afterburners" <br /><br />Suggest reading the discussion page for the article too. Lots of good commentary. It is still clear that, even if you allow other planes on the supercruise list, the F-22's capability at it is head and shoulders above everybody else, particularly carrying one's full weapon load.<br /><br />This seems to be the important thing: supercruising fighter A with full weapons load meets slightly supercruising fighter B that is doing so without any weapons load. Which one wins the dogfight? Obviously the one with the weapons.<br /><br />Soviet fighters got high speed/high thrust by having big fat afterburners. Their range stunk.<br /><br />On Military vs A/B: some think "military power" is the highest non-A/B throttle position. My experience working on the F-15 and F-111 for years says that military is A/B, for two simple reasons:<br />a) outside of the SST's only military planes have afterburners. You can buy, in many instances, the same engine on the civilian market without the afterburner and get the peak non-A/B thrust. Peak non-A/B thrust is typically about 70% of "Military".<br />b) it said so on the throttle and in all my manuals.<br /><br></br>
I don't think that a supercruise is that much of a problem to achieve. And it ain't a big deal if you're looking for an air-launch system. <br />I'm much more impressed by planes which supercruise for long periods of time on afterburners. Supercruise or not, you probably wont catch it 
.<br />Yes, the Raptor is clearly the best of all when it comes to supercruising, but really...its cost is 2-3 times bigger than most of the other planes.<br />Anyway, I found a Mig-17 or 19 some 30 miles from my home, while driving. Not really sure here about the type, it was darkish. It's parked inside of a small and abandoned Yugoslavian SAM and radar outpost which is not guarded(possibly mined, abandoned for some 15 years). Now... If I could only get my hands on that MiG. Its not guarded and its in the wild. I'm only interested in its engine. I have become addicted to jet and rocket engines, and which better way to learn its ways than studying a "real" one. <br />BTW, is there any material that can be found on the net which is good for learning, but in depth, the construction and physics of jet and rocket engines? Something comprehensive and mathematical...
.<br />Yes, the Raptor is clearly the best of all when it comes to supercruising, but really...its cost is 2-3 times bigger than most of the other planes.<br />Anyway, I found a Mig-17 or 19 some 30 miles from my home, while driving. Not really sure here about the type, it was darkish. It's parked inside of a small and abandoned Yugoslavian SAM and radar outpost which is not guarded(possibly mined, abandoned for some 15 years). Now... If I could only get my hands on that MiG. Its not guarded and its in the wild. I'm only interested in its engine. I have become addicted to jet and rocket engines, and which better way to learn its ways than studying a "real" one. <br />BTW, is there any material that can be found on the net which is good for learning, but in depth, the construction and physics of jet and rocket engines? Something comprehensive and mathematical...so...what's stopping you?<br /> throw a lot of rocks in the area and if there are any mines they will go off <img src="/images/icons/smile.gif" /><br /><br />jk, don't fo anything stupid. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>
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